Todays Recommended link...

 As there is a lot of wrong information out there someone has put this page up with all the history. Invest some time reading up on all the past and present PS3 Jailbreak methods. Definitely loads of information on there to keep you busy for a long time.

Heres the link
PS3 Jailbreak History


Quote...

Original exploits depended on the built in Java of BlueRay menus. Java on the blueray had been too limited and only a small buffer overflow was discovered. Linux had been added to the PS3 around this time with the the introduction of otherOS. The beauty of Linux had been the ability to probe the PS3 system and firmware. A method was found of glitching the memory of the PS3 to access the hypervisor was discovered by geohot. The ps3 scene was outraged by what happened next! The things was first regarded as a bad april fools joke turned out to be real with the removal of otheros All hope seemed to be lost and the scene was getting much quieter again. Upon getting the blame for otheros beign removed by sony Geohot leaves the scene.