Good news for phans of phun: the Phun physics simulation software is now available for Windows, Linux and Mac OS X! Here's a video demonstration (with music, so watch out) of what Phun is all about:

How to have Phun:

Download and install the software Check out some of the pre-made demos (File... Load scene). Make your own. "Clear scene" then use the Plane Tool to make the ground. Press the green "Play" button to make the scene active. Switch to the brush tool and make a triangle. Make sure to close the loop or it won't appear. Make a big board, like a see-saw on top of the board. Use the brush tool to put "rocks" on either side of the board. Use your scroll wheel to pan in and out. Drop a big rock on one side of your see-saw and watch all the little rocks fly around. Left-click on the sky to pan the world around, and left-click on an object to 'do' stuff to it -- change the big rock into water, for instance. If you screw up any of this, control-Z is Undo. Use it early and use it often.

This is the kind of thing I wish existed when I was teaching high school. If you have kids, or if you know kids, or if (like me) you are just immature and like to knock things over, you should check this out.

~Jeff