This is a hyper-simple game, but is great for a couple hours of killed time. It's called "Planarity" and is available at http://home.cwru.edu/~jnt5/Planarity/. A couple other folks on LJ and elsewhere have posted about it, but the nutshell is you're given an ever increasing number of vertices on a polygon, interconnected randomly. Your job is to move the vertices so none of the connecting lines overlap.
It's not unlike those earth-games human pretzel knot games.
I just finished Level 4, at 3:08 for a time.
Enjoy :)
