Games you've completed time and time again.

[JustThatGamer]

Some games from this generation:

• God of War III: 8 times. (9th play-through soon, then 10th before IV releases).
• God of War 1, 2, COO, GOS: 5 times each. (Replaying all soon so it'll be 6 each).
• Gears of War 1: 7 times.
• Gears of War 2: 7 times.
• Gears of War 3: 2 times. (Replaying with a friend on co-op so it'll be 3).
• Mass Effect 1 & 2: 3 times. (Replaying both before I get3, so it'll be 4).
• Alan Wake: 3 times. (Replaying before I get American Nightmare).
• Bioshock 1 & 2: 2 times. (Replaying both before I get Infinite).
• Dante's Inferno = 3 times. (Purely for achievements, also my brother paid me to play it for him for achievements). 
• Castlevania: LOS: 2 times. (Will replay again so it'll be 3).
• The Elder Scrolls IV: Oblivion: 2 times. 
• Fable II: 3 times.

I hardly ever trade in my games because I like having a fairly-large collection, but there aren't many games I can be bothered to replay.