It's not just protein folding, but the powerful playstations can be used for other computationally demanding assignments such as ligand docking. I just read that Simbiosys has released a version of their docking software for the PS3.
To lower the cost and power consumption typically associated with compound-library-screening programs, SimBioSys has also released eHiTS Lightning. This package combines the 2009 eHiTS software with IBM's Cell/B.E. chip multiprocessor, found in the Sony PlayStation 3, to achieve a 10-fold increase in computational speed. The PlayStation 3 hardware (shown) replaces some of the expensive computer infrastructure required for virtual screening programs, opening up computer-aided drug design to smaller companies previously unable to afford it.Pretty damn cool!