I have switched over to Maxwell’s Demon. It currently has a hot molecule (in red) and a cold molecule (in blue). You don’t have to watch very long to determine that molecules can change temperature when they collide.  I will need to take that into account. It would be fun to show a distribution graph alongside the game. I will do that when I have time. I suppose “losing” would be when the molecules all reach some type of thermal equilibrium.

Note to those having trouble with items sticking to walls (as I was). Set

• Box2D.Common.b2Settings.b2_velocityThreshold = 0.0;

first thing to avoid this problem.