yer you can you go on
http://www.getmiro.com/ click on the green icon "download miro 2.0" then once installed you can downlad all clips off youtube.com, etc... the only catch is they only last like 5 days or some shit, so i would say download as well a program called "prism"
http://www.nchsoftware.com/prism/ it is a video converter, and convert them to something like .mpg and then they are yours to keep, hope this was a big help cheers, pat (aus.)