I only keep the best of the best games, usually those that get supported with additional (wothwhile) content or have an editor to mess around. Starcraft 2 (Battlenet), DA (editor) and Alpha Protocol (because of high replayability?) will be those that I keep. But the rest I sell back. What point is there to keep a game you have finished in 7 hours and already forgot the next day? It's precious money I get back for selling it. Like Divinity 2. Good game, but I'll never touch it again. Goes back to ebay. Through this, I save money for future purchases.