Very, very cool dude! For the first implementation of physics for Minecraft, that's a pretty darn good job. I wonder if that could be tweaked to make water flow and splash better or lava to behave like a heavy, syrup-like mass?
I also wonder about the limits of a java based game. I wish Minecraft were written in C+ to make more efficient use of game code not only for graphics, but for physics like this.
Phyzzle is a 4-in-1 pack of the latest ModLoader, TooManyItems, Phyzzle, and MADS. ModLoader is necessary to be bundled in because Phyzzle touches a few base Minecraft classes, TooManyItems is just plain useful, Phyzzle is the underlying glue logic, and MADS is an updated version of MADS that takes advantage of rigid body physics when it can.