Oh, I flexed the hell out of my google fu tonight. You didn't think I was going to leave all the wacky finds out of this, did you?
First, an a cappella rendition of “Harder, Better, Faster, Stronger”. Live, so deal with the crowd noise as you will:
Second, a fan video for the Kanye West “Stronger” that samples those Daft Punks (which, by the way, samples this song) which gets my nod just for the devotion on display:
Next, someone went through the trouble of staging a Sims 2 video for the Eiffel 65 song. And it's actually good:
Finally, Lou Bega gets the crappy WoW machinima treatment. Because, really, it's Mambo Numbah Five, what do you expect?
Plenty more gems out there, so find your own.