Wirehead Studios

Mine are:

-Shout 2000 from Disturbed
-and a close second is Take on me from Reel Big Fish

Hmm... I tend to usually like the originals better than cover versions, but the (older) covers Metallica has on Garage, Inc spring to mind.  I have most of those from the non-compilation albums.  I was rather disappointed when Kill 'Em All didn't have Blitzkrieg and Am I Evil? since they were on the cassette version, so I just ripped them from Garage and made my own "classic" version of the album.

Another one I kind of liked was Bruce Dickinson covering Sabbath Bloody Sabbath, but then I pretty much like all of Bruce's stuff.

Favorite cover? I'm with Pho on preferring originals over covers.. but.. I do have covers that I like.

Toppers tho would be:
Anarchy In The UK - Megadeth (originally done by the Sex Pistols)

Blitzkrieg, The Small Hours, & Last Caress/Green Hell - Metallica (originally done by Blitzkrieg, Holocaust, & Misfits)

Cum On Feel The Noize - Quiet Riot (originally done by Slade)

I Want Out - Hammerfall (originally done by Helloween)

Dark Side of the Moon - Pink Floyd (DOH!)
Storia di un Minuto - Premiata Forneria Marconi
Scenes from a Memory - Dream Theater

Top 3.

Subject to change, but at the moment it's Polysics's cover of "My Sharona" by The Knack.

Album cover art, meanwhile, it has to be the Floyd's "Dark Side Of The Moon". Simplicity is the key ...

I've always been fond of Veruca Salt's cover. It's slowed down and almost humorously unenthusiastic. "My, my, my, my - woo." :P