Orbiter with UCGO addon
Orbiter: http://orbit.medphys.ucl.ac.uk/orbit.html
UCGO: http://orbiter.dansteph.com/index.php?disp=d

You may watch a video here
http://www.youtube.com/watch?v=Ukb33V0gSWs

and also you may like to download this video
http://www.megaupload.com/?d=L6CKG0NU