The latest company to face hacking is TiVo, which markets a digital video recorder that saves TV shows on a hard disk. Some customers have begun tinkering with the boxes to add a second hard drive, letting them skirt an official upgrade, which is more expensive and inconvenient.
Hacking has become a big issue for makers of devices that are engineered and marketed to perform specific functions but can be converted to other uses by the technically savvy. Earlier this year, hackers found a way to turn Netpliance's I-opener Internet appliance into a Linux-based PC.
Unlike the well-publicized Netpliance hack, which eventually led the company to revamp its business model, TiVo customers who modify their digital video recorders still use the company's service, which includes on-screen, interactive program guides.
"We're not trying to circumvent what the actual unit does," said Mike Hill, a software consultant in Cincinnati whose Web site offers free instructions for modifying TiVo. Hill said he added a second hard drive to expand his 14 hours of storage, instead of paying for a $300 upgrade. Plus, he couldn't part with the device long enough to get it upgraded.
"Once you've got a TiVo, you don't want to ship it off," Hill said.
For the past month, Hill has offered his BlessTiVo instructions, which help people modify the Linux-based TiVo unit to recognize a second drive. Hill said more than 1,000 people have downloaded the instructions from his site, but he estimated that probably fewer than 100 people have actually added a hard drive.
Such a move voids the warranty but is apparently not a big concern to TiVo--or to Sony and Philips Electronics, which make the devices.
"There are people out there that will hack into anything," said Rebecca Baer, a spokeswoman for San Jose, Calif.-based TiVo.
She added that her company has not received requests from its hardware partners to try to make it more difficult to modify the device.
While the current hacking apparently is not of much concern to TiVo, other modifications might be. Hill said he has heard of people who are working to crack TiVo's proprietary format for storing video files, along with other modifications that might be less palatable to TiVo and the rest of the entertainment industry.
Hill said he would be interested in trying to convert the unit to play MP3 files, using the TV as the interface and stereo speakers to play the music.
Software is also coming out that will offer a recording service similar to TiVo but via a PC, potentially allowing TV shows and movies to be saved to CDs or other portable media.
People are bound to play around with these new devices, Hill said, particularly if they are based on Linux.
"If it has standard PC equipment in it," Hill said, "you're going to have people try and figure out what makes it tick and what they can do with it."