Here are some that come to mind:
Arcanum: Of Steamworks and Magick Obscura (2001)
Hitman 2: Silent Assassin (2002)
Hitman: Contracts (2004)
Hitman: Blood Money (2006)
Freedom Force (2002)
Max Payne (2001)
Max Payne 2 (2003)
Medieval: Total War (2002)
Medieval II: Total War (2006)
Star Wars: Republic Commando (2005)
Star Wars: Empire at War (2006)
Vampire The Masquerade: Bloodlines (2004)
Warhammer 40,000: Dawn of War (2004)
I agree on Mafia as a must-have - a great game in the GTA style (and the best ever GTA "clone"). Half-Life 2 and both JK2: Jedi Outcast & JK3: Jedi Academy are also must-haves.
Last edited by DarthParametric; 05-10-2012 at 06:09 AM.