The batman games, akrham asylum and arkham city.
Crysis
Bioshock
Darksiders was fun.
Dark Void was as well. JETPACK!
Metro 2033, it was a completely overlooked game, as it was released on the same day as MW2. FUCKING AWESOME.
Singularity
Splinter cell
Unreal tournament 2004 and III
IMO, these are my favorite 1st person/3rd person shooters