In case anyone wants to play (or develop levels for) numptyphysics on Windows machines, I've done a very quick port to WIN32. You can find the patch against SVN r42 and a compiled .exe package there:

http://thpinfo.com/2008/numptyphysics/

The data files are placed in the subfolder "data/", relative to where the exe is put. You can put downloaded levels there and when you save a level you have modified or created, you can copy it from the "data/" folder (the L99_... file, same name as the standard numptyphysics on Maemo/Linux).

Thanks to Tim for this great game!