Not all of these games were huge commercial success stories, but I'll list the Playstation games I didn't play.
- Socom
- Syphon Filter
- Dark Cloud
- Ape Escape
- Almost every JRPG, except Final Fantasy.
As for this gen .. I have not played any of the following
- COD
- Dead Space
- Any sports game that's big in America (NFL, NBA, NHL, Baseball, etc).
Playstation = The Beast from the East
Sony + Nintendo = WIN! PS3 + PSV + PS4 + Wii U + 3DS