The 20-year-old hacker best known for cracking Apple's iPhone says he's done it again, this time with Sony's PlayStation 3 (PS3).

In a blog post, George Hotz said that after a five-week effort, he'd finally managed to run his own software on the PS, which typically only plays digitally signed software that is approved by Sony. "I have read/write access to the entire system memory, and [hypervisor] level access to the processor," he wrote. "In other words, I have hacked the PS3."

He pulled off the feat using "very simple hardware, cleverly applied, and some not so simple software", he added.

Hotz received widespread media attention in the US in 2007 when he developed a technique that allowed the iPhone to run on any wireless network.

Hotz's new technique could allow PS3 users to run new, unauthorised software on their systems. Such software could include the Linux operating system or older PS2 games, which don't work on the PS3. But the hack could also give gamers a way to run pirated software on their systems too.

PlayStation fans will have to wait some time before they get to see Hotz's code, however. In his blog post, he said he isn't revealing how he pulled off his trick just yet, in part because he's worried that Sony may find a way to disable his technique.

That's what Apple tried to do with the Jailbreak hack. The company has repeatedly disabled the Jailbreak code in software updates to its devices, but hackers have responded each time with new techniques to keep the phones unlocked.

Hotz did say that he was hoping to find and publish the device's decryption keys, which could help others develop and run unauthorized software for the machines.

Sony could not be reached immediately for comment.

See also:

Apple iPhone 3GS review

PC security advice