When you delete a file from a standard desktop computer, the file first gets moved to the "recycle bin" or the "trash," which means only that you've placed the intact data in a new directory. You erase the file when you empty your recycle bin. But even then, much of the information remains on the hard disk. Exactly how much depends on the type of computer you're using and which operating system you have.

They first "delete" a file in the conventional sense, and then they overwrite it with zeroes, ones, or random data. Finally, they erase the record of where the original file was stored on the disk. More advanced programs might overwrite the original with something less conspicuous than a string of zeroes, like an ordinary text file.

But even if you do wipe your disk successfully -- and overwrite each of your deleted files -- traces of the original data remain. Writing to a magnetic disk is not as precise as one might think; when you overwrite a file, the new version doesn't completely cover up the old. The leftover data can be read out with certain imaging techniques, like magnetic-force microscopy and magnetic-force scanning tunneling microscopy. Computer forensics experts say it's possible to recover data beneath dozens of layers of overwriting, and privacy fanatics talk about wiping their disks up to 35 times over to be absolutely safe.

Internet file-sharing services will be held responsible if they intend for their customers to use software primarily to swap songs and movies illegally, the Supreme Court ruled Monday, rejecting warnings that the lawsuits will stunt growth of cool tech gadgets such as the next iPod.

The unanimous decision sends the case back to lower court, which had ruled in favor of file-sharing services Grokster Ltd. and StreamCast Networks Inc. on the grounds that the companies couldn't be sued. The justices said there was enough evidence of unlawful intent for the case to go to trial.

"We were horrified," Georgia-Pacific spokeswoman Robin Keegan said. The company ? maker of Dixie products, Brawny paper towels and Quilted Northern toilet tissue ? pulled all of its Yahoo advertising and hasn't returned.

Internet advertising is surging to record highs as the percentage of homes with high-speed connections rises and growth at more traditional media atrophies. Online ad sales topped $2.8 billion in the first quarter, up 26% from 2004. Sunnyvale, Calif.-based Yahoo posted 2004 revenue of $3.6 billion, most of it from advertising.

Some advertisers, however, are realizing just how little they know about what their money is getting them. Users contribute all or most of the content at many increasingly popular types of sites, including discussion boards, social-networking companies and blogs.

Most companies have little control over where their ads run because they buy online ad space in bulk through brokers who purchase spots on various websites. Individual ads often are placed by computer programs that match up keywords so that, at least theoretically, car ads pop up in discussions about cars.

Exceptional Readability : Roughly twice the contrast of a reflective LCD, EPD's can be easily read in bright sunlight or in dimly lit environments and at virtually any angle.

Low Power Consumption: In addition to the fact that no backlighting is required, the display also has an inherently stable "memory effect" which requires no power to maintain an image - both of which drastically increase the battery life. The result is 1/100 the power consumption of traditional display options.

Versatile, Flexible Form: E Ink Imaging Film allows product designers to create entirely new designs that were never possible before. This thin, flexible display can be used to create curved, eye-catching shapes.

In fact, it's one of the chief challenges facing the best-known Wiki, Wikipedia, an online encyclopedia where any visitor can add, change and erase someone else's entry.

Some contributors have attempted to impose their personal viewpoints ? for instance, by replacing an article on abortion with the word "murder" written 143 times.

"The current situation is getting back to the '70s and '80s, where IT workers were the basement cubicle geeks and they weren't very well off," said Matthew Moran, author of the six-month-old book Information Technology Career Builder's Toolkit: A Complete Guide to Building Your Information Technology Career in Any Economy.

"They were making an honest living but weren't anything more than middle-class people just getting by," Moran said.

Depending on the exact details, Google's move could potentially threaten eBay's successful PayPal service, which generated $233.1 million, or 23% of eBay's revenue in the first quarter. PayPal has been widely adopted by buyers and sellers on eBay's auction marketplace as a way to pay for purchases. Recently, eBay has been trying to expand PayPal's presence as a payment system for other Web sites. In the first quarter, 71% of PayPal's revenue came from eBay auctions, the company says.

"It could be a pretty big negative for eBay if it happens," says Safa Rashtchy, Internet analyst at Piper Jaffray. Mr. Rashtchy said he believes Google is also working on a classified-listing service, which also would compete with eBay, San Jose, Calif.

The United States has seen a reversal in a long-term trend that saw women increase involvement in technical fields such as math and science. From the mid-1980s to 2001, female enrollment in math and science doctoral programs in the United States jumped 20 percent, according to research cited by Rosser.

But in a more recent study, enrollment of women in computer science between 1998 and 2004 fell 80 percent, compared with a 32 percent drop for men and women combined. While the dot-com bust explains part of the retreat, Rosser and other researchers believe the disproportionate drop underscores the frustration women feel over cultures that are often less than welcoming to women in technical fields.

ComScore Networks' global visitor numbers tell the story. In 2002, WSJ.com was averaging around 1 million unique visitors a month, FT.com 1.3 million, Fortune.com 1.7 million and Forbes.com, 1.7 million. Three years on and WSJ.com is averaging around 3.3 million unique visitors; FT.com, which gated much of its content in mid-2002, is around 1.8 million; Fortune.com, which allows viewers to see a little free content before shuttling them to a subs sign-up form, averages 1.3 million. And Forbes.com? It?s at about 7.8 million.

Mr Pait thinks that although many people are already living an accumulative terabyte lifestyle, in about five years PCs will have five terabytes of storage on board.

One terabyte is the equivalent of 1,024GB, enough to hold more than 240,000 songs at the standard encoding rate for digital music files.

This will only be possible because of perpendicular recording methods, which Seagate, Hitachi, and others, have to exploit.

Yet this cooperative force may spread beyond such easily shared commodities as information, knowledge, and media. People are starting to use the Net to pool tangible goods as well. In a sense, Skype enables people to share computer hardware. Thanks to the Web's ability to serve as a meeting ground and scheduling coordinator, it's becoming economical to share cars, for example. Services such as Zipcar Inc. and Flexcar let members use the Net to reserve one of a fleet of autos in crowded cities, almost on demand, for an hourly fee.

What's driving all this togetherness? More than anything, an emerging generation of Net technologies. They include file-sharing, blogs, group-edited sites called wikis, and social networking services such as MySpace and Meetup Inc., which has helped everyone from Howard Deaniacs to English bulldog owners in New York form local groups. Those technologies are finally teasing out the Net's unique potential in a way that neither e-mail nor traditional Web sites did. The Net can, like no other medium, connect many people with many others at the same time.

Among the five major search sites -- Google Inc., Yahoo Inc., MSN, America Online Inc. and Ask Jeeves Inc. -- Yahoo and Ask Jeeves were cited for making their headings fainter and their disclosure statements harder to find.

"If you want to call attention to something on a page you put headline above it, [but] you don't make it smaller and more faint," said Beau Brendler, director of Consumer Reports WebWatch.

Yahoo also received the most criticism about its paid inclusion program, since it is the only engine among the top five to still use the practice, and because one way it charges included sites is based on the number of clicks on their listings.

Time Warner (TWX ) has decided that it's go-for-broke time at AOL, as the beleaguered online division launches a last-ditch gamble for survival. To generate growth even as its Internet service loses subscribers, the online company is launching one of the most radical strategic shifts in years -- throwing open its content for free in a bid to cash in on a gusher of online-ad revenues.

The refurbished aol.com is taking a different approach than the other big portals, such as Yahoo! (YHOO ) and Microsoft's (MSFT ) MSN, which hit their stride before broadband usage took off. AOL's site, to launch in July, will put streaming video and audio content front and center -- including exclusive live concerts, celebrity interviews, and film shorts.

Rapid prototyping machines work by building a succession of layers, either bonded by a laser or held together by alternating layers of glue.

The key feature of the RepRap is its ability to print electrical circuits by squirting a metal alloy with a low-melting point from a heated nozzle.

The machine could build items ranging in size from a few millimeters to around 30 centimeters, such as plates, dishes, combs and musical instruments.

Larger or more complicated items could be assembled from smaller parts, and by adding extra parts such as screws and microchips.

Dr Bowyer said all that would be needed for a machine owner would be to buy the plastic and low-temperature alloy for a few pounds, and items could then be created in a few minutes or a few hours depending on their size. Designs for items could be bought ? or downloaded free ? from the web. Alternatively, people could create them for themselves on their own PCs.

He said that he would publish the 3D designs and computer code for the machine to replicate itself on the web over the next four years as they are developed, until the entire machine could be copied.

He said that he has not taken out a patent and will not charge for creating the design for the machine. "The most interesting part of this is that we're going to give it away," he said.

"At the moment an industrial company consists of hundreds of people building and making things. If these machines take off, it will give individual people the chance to do this themselves, and we are talking about making a lot of our consumer goods ? the effect this has on industry and society could be dramatic."

The machines would be about the size of a refrigerator, and would self-reproduce by making a copy of themselves, part by part. These parts would then have to be assembled manually by their owners.

One in five kids has been bullied or threatened via their mobile phone or computer, according to a study by U.K. children's charity NCH.

Bullying by text message was the most common form of abuse reported, with 14 percent of kids interviewed saying they had received upsetting messages on their mobile phones.

The survey, titled "Putting U in the Picture (PDF file)," collated responses from 770 youngsters ages 11 to 19. One in 10 said someone had used a camera phone to snap their picture in a way that made them feel uncomfortable, embarrassed or threatened. Of those, 17 percent believed the images had been forwarded to others.

Not everything about blogging is a good thing. Blogging has led to a rise in cyberbullying in schools where blogging allows kids to easily bully other kids and mock them. They also use digital photos for the humiliation of classmates. Kids are quick with technology and have little trouble with the latest photo sharing and blogging tools.

The molecule cluster is 10,000 times thinner than a human hair, and marks another step forward in nanotechnology, the science of atoms and molecules that is set to transform medicines, technology and even food in years to come.

Lead researcher Dr. Lee Cronin told the Sunday Herald: "Data storage hits the wall at a certain point companies are spending billions cramming more memory into smaller space, but it can't go on forever with current technology.

"What we have come up with is a molecule with the potential to pack in 10,000 more 'storage units' into a given area than is currently possible."

The new pornography suffix was among 10 under consideration by the regulatory group, which also recently approved addresses ending in "jobs" and "travel."

ICM contends the "xxx" Web addresses, which it plans to sell for $60 a year, will protect children from online smut if adult sites voluntarily adopt the suffix so filtering software used by families can more effectively block access to those sites.

Several versions of the message have been caught by anti-virus and mail-filtering firms but all bear the same fake information about Bin Laden's arrest.

All versions claim that TV news channels such as CNN and the BBC will soon be reporting the arrest and showing more pictures.

One version of the malicious message claims to contain pictures grabbed from a military TV channel. Another directs people to a website holding videos of the capture.

The auto giant has set up a division to make the company a powerhouse in the potentially lucrative sector of robots for household use.

In 2010, the automaker intends to start selling next-generation household robots to help people receive visitors, raise children and provide nursing care for sick and elderly patients, company officials said.

America Online, with 28 million members, has assigned a full-time employee to handle next-of-kin requests. Before releasing account information, the company requires a copy of the death certificate and documentation proving the person requesting the e-mail information is the legal beneficiary or the estate representative, said America Online spokesman Nicholas Graham.

MSN Hotmail will provide account contents on CDs or floppy disks to relatives of deceased members after it verifies the legitimacy of the request, said Brooke Richardson, MSN lead product manager, in a statement. ``We have tried to institute a policy that is very focused on privacy, but at the same time honors the requests of bereaved family members.''

After Lance Cpl. Justin Ellsworth of Michigan was killed Nov. 13 while inspecting a bomb in Iraq, his father, John Ellsworth, wanted access to his son's Yahoo email account. But Yahoo, whose policy is to terminate email accounts upon a user's death, would not give him the material until a probate judge ordered the Sunnyvale company to do so.

Danny O'Brien of the Electronic Frontier Foundation, a San Francisco non-profit that often gets involved in digital-privacy issues, said it's difficult to find the right balance between personal privacy and a family's desire to get all of a loved one's possessions.

``We are sympathetic to the pain families go through,'' he said. ``On the other hand, there are a lot of things people want to keep private from their close relatives. You need to have some way to do that.''