PSP games

[Juventus]

Disgaea: hour of darkness/Jeane D'Arc for your time sink strategy rpg

Metal Gear Solid: Peace Walker for your action/stealth game.

Prinny: can I be the hero for your platformer

God of War games: for button mashioning epic action games.

Persona 3 for your rpg

GTA games for sandbox action

 

[Thaius]

Off the PSN:
Final Fantasy VII
Vagrant Story
Crash Bandicoot (1, 2, 3, and CTR)
Spyro the Dragon (1, 2, and 3)

Actually for the PSP:
Crisis Core: Final Fantasy VII
Crush
Jeanne D'Arc
Daxter
Puzzle Quest: Challenge of the Warlords

... I think that's all I can come up with. Not too many good games on the thing, and not many good exclusives at all. Good luck.