Check out Flvix, a new online service that lets you convert any video from Google Video or YouTube into the .MP4 format – so you can watch it on your iPod.
[ Update: Jan 2nd, 2009 ] – Google video and YouTube are the same now, and flvix has become a porno site. Things change.
To convert videos as described above, try out Vixy.net. If it’s turned adult by the time you click on this link, good luck!