PSP mods started surfacing online almost immediately after the gadget's release. One of the notable early hacks came when someone discovered that the creators of the PSP's hovercraft racing game, Wipeout Pure, had included a simple Web browser inside the game. Intended for downloading game content, the browser could be redirected to other sites by the technically savvy. Hackers began gleefully surfing the Web with the tiny handheld, and even playing rudimentary online games such as Tetris.

But the online exploits were just the beginning. Hackers soon found out that with a bit of trickery, it was possible to run code directly from the PSP's memory stick. Sony included that feature so that it could distribute minigames or expansion packs for the PSPs. But hackers saw another application: home-brewed games. Rather than spending thousands of dollars for a PSP game-development kit, someone could simply code, say, a chess game on a PC and load it on a memory stick.

While some hackers circumvented the copyright protection scheme to run home-brewed programs off the memory stick, others busied themselves with hacking Sony's proprietary media discs, which store PSP games and movies. Before long, intrepid gamers could watch home movies as well as use home-brewed software. "Very little of the motivation is about playing pirated games," Sample says. "It's about playing the cool programs that people have written."

An example is PSPKick, a free download that converts the PSP into a drum machine. Users can create a rhythm, then change the volume and pitch of the notes, and then save the sounds they make as .wav files and incorporate them into professional sound-editing programs. Graphic designer Nathan Wray and his friend Noah Vawter, a graduate student at the MIT Media Laboratory, developed the software, which they're distributing online [see photo, "Music Mod"]. Mods "are a great way for people to produce something without having to go through the painful and extremely costly process of getting rights and a development platform," Wray says. Besides, he adds, "the more people making music, the better."

Sony, not surprisingly, isn't pleased. With the game industry losing an estimated $3 billion per year to piracy, Sony is eager to plug any holes on its new machine that could be used to copy or run pirated games. And Sony has a solution: firmware. The North American version of the PSP, for example, shipped with firmware Version 1.5, which was soon followed by two upgrades. To entice more gamers to update their machines, Sony packed its 2.0 upgrade with new features, including the "official" Web browser.

The 2.0 firmware also prevented gamers from playing homemade code. So, of course, the hackers fought back. A group of PSP hackers calling themselves SonyXteam disseminated a program called SXT Version Changer, which downgrades the firmware. But the cat-and-mouse game continues, with Sony's recent release of firmware Version 2.5.

For hackers it may soon be "game over" after all. "Eventually," says the webmaster of PSP Updates, "Sony will close enough of the loopholes in their security to prevent easy access to the system. At this point, I fear that people will have to make a choice to either cease updating their systems and keep the ability to run home brew, or to update the systems, lose the ability to run home brew, but be able to play newly released official games." [See photo, "Update vs. Home Brew."]

And that, hackers say, is the heart of the problem. The success of hack-friendly games such as Doom and Quake shows that the PSP could benefit from being more open, they say. But Sony isn't going there yet. "We have a rollout plan already developed and scheduled for each upcoming feature of the PSP, and outside influences haven't affected this process," Sony's Koller says. "While we recognize the creativity of some of the available mods, we are diligently following our schedule for official updates to the PSP system."