Sony patents add-on device to play PS2 games on the non-PS2 compatible PS3 models. Originally Sony took out PS2 compatibility as a way to save money and now want to have consumers pay for the ability to play PS2 games for any PS3 model.
The device itself is basically a mini-PS2 and doesn't use the PS3 CPU and GPU to play PS2 games since it has its own decoders and processors.
http://gamrfeed.vgchartz.com/story/8...ayback-device/