SpaceChem
This morning I completed the final level of the video game SpaceChem. Many people had recommend this puzzle game to me as one that I would like and they were correct. Some of the game mechanics remind me of the board game RoboRally, which I also enjoy. As the game progresses though it turns into a complete visual programming language with switches and branching letting you create very complex behavior from simple primitive operations. And like most programming you can spend time optimizing your algorithms against either space (reactors and/or symbols used) or time (cycles used). I didn't spend much time going back to optimize my solutions as the 44 hours (wow looking at RescueTime scares me sometimes) it took me to beat the game was enough of a distraction :)