I'm on slow rural dial-up, so seldom even try to download youtube videos--takes FOREVER. That said---this AM, the Saturday "Today" show showed a video they mentioned had 'gone viral' on Youtube, of a dog welcoming her soldier-owner home from Afghanistan. It was shot in '05, but just put up on Youtube, they said. Made me tear up; there is NOTHING that loves you unconditionally more than a dear dog!! I just LOVED seeing it!
(edited to add: the one shown on 'Today' was the first on on the link Daryl posted; if I could, I'd watch ALL the others, based on how great that one was....)
Margo