If you want them on your ipod you can put 'em on there in an .flv video format, if your Ipod is video capable.(can't remember what format Ipods take though)
KeepVid: Download videos from Google, Youtube, iFilm, Putfile, Metacafe, DailyMotion! just paste the url of a video in there and you'll get your .flv video. Onyl legal way I know.(at least I think keepvid is legal)