I’m a sucker for cheap flash games, so I tend to stay away. I found one on National Geographic’s page though, and it’s cool. NG accepts photo’s from people, it’s called Your Shot. Something they’ve done with those photos is build a Jigsaw Puzzle app for them. I first found it about a week ago, and they’ve probably added 60 photos since then.
The puzzles are fairly small, my average time for putting one together is about 5 minutes. The pictures are all amazing, and it’s a nice little mental break when I’m working or something.