Phun learning physics [www.acc.umu.se]

Phun is a 2-D physics modeling environment, Windows only. A Mac OS X version is in the works according to the FAQ. It looks like another tool in the spirit of Squeak Etoys, Scratch. Scratch is generally geared more towards making games, while Etoys can be used for simulation as well as games. Of course, in any programming environment you can create anything with enough imagination.
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