1. Football Manager 2012 - Played it a lot. My current save's gametime has "56 Days, 9 Hours, 33 Minutes" listed. Addictedness Rating (yes, they have this) is "Nothing to see here, move along..."
2. Skyrim - Played it through to end.
3. XCOM: Enemy Unknown - Played it through to end.
4. Thief Gold - Played a few levels.
5. Thief 2 - Not yet played.
6. Thief: Deadly Shadows - Not yet played.
7. Portal - Not yet played.
8. Dota 2 - Not yet played (gifted to me).