World of Goo [Steam store page]
I'm not madly in love with this game, but it's a decent way to pass the time. The puzzles are usually fairly easy, though sometimes it is hard to execute them because of the way the AI makes goo run around the structure

Deus Ex: Game of the Year Edition [Steam store page]
One of the best FPS I've ever played - fantastic story and detail. Each play-through you'll find new areas, people, and story that you missed before. Highly recommended

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