A member of Neogaf has put together a list of PS3 titles that use the Cell's SPE's, it is alleged that the majority of the PS3's processing power is located in the SPE's and without utilizing them it is pretty much like developing for a normal single PC or Mac CPU. Use of the SPE's are very much on the rise and are very beneficial as evident by the quality of the likes of Resistance, Motorstorm and Heavenly Sword.