TiVo executives believed that the company could attract hackers as long as it stayed one step ahead of them on the copyright front. To achieve this, TiVo used a variety of methods to hide content files, including leaving them unlabeled and creating an elaborate, proprietary file system that split the recordings into multiple small files spread across the hard drive. And with each software upgrade, TiVo hid the content in new ways, Bulwinkle says. Since there didn't seem to be much interest in getting access to the content anyway, TiVo thought any copyright concerns were negligible.

Enter Tridgell, a well-known Australian hacker and the creator of Samba -- an award-winning software program that allows Windows and Linux machines to interact on a network. In November 2000, Tridgell e-mailed TiVo and told the company that he'd figured out the file system.

"It took about a week of evenings," he says.

He didn't hack the TiVo with illegal intentions. TiVo's normal service included a listings guide that was useful only in the United States -- the guide had no information on scheduled programming in Australia. Tridgell unlocked the file system to build an alternative; the software he wrote essentially dialed into his own Web site with Australian programming information rather than into the TiVo servers. Even after bypassing this crucial element of the TiVo package, however, Tridgell says, he still pays TiVo's service fee. "It's the decent thing to do."

Tridgell compounded TiVo's problem with a related hack. He wanted to send shows to other TVs in his house, so he added a way to transmit the copied programs through an Ethernet port that connected his TiVo to his computer network and then to his other TVs.

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Tridgell immediately understood the legal and financial ramifications of what he'd done. He had the potential to severely and single-handedly injure TiVo. The Ethernet hack alone could threaten the partnerships that TiVo had struggled to forge with broadcasters in the first place, and the alternative-guide software undermined a key source of revenue.

"Their business model is somewhat shaky because they're selling something that's already available," Tridgell explains. "What you buy for $9.95 is the ability to do a daily callback [to TiVo's servers] where you get the guide data. That's what makes a TiVo different from a regular VCR. So if I released [the source code that lets people build their own guide] there would be no reason to subscribe to TiVo."

Tridgell wouldn't normally care much about the business model of a company whose product he hacked. When he decided to develop Samba, for instance, he didn't ask Microsoft for permission, nor did he go to Sony when he developed Linux drivers for Vaio video cameras.

But TiVo didn't act like Microsoft. It used a Linux-based operating system in its boxes and encouraged tinkering, so Tridgell decided to "do the decent thing" and talk to TiVo about the hack. He visited the company's Alviso offices in February. After some discussion, he decided to keep the hacks under wraps -- although he did reveal their existence to the TiVo community.

"They requested that I delay the release, for all sorts of reasons," he says. "I didn't need permission to release what I'd built, but I went to them because I thought they were doing right by the community. So the main thing I said was that I wouldn't release the guide system. And I agreed to postpone the video extracting software."

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