A couple of mine
"Talkin' About Revolution" (Tracey Chapman)- Niteblind
"Crazy" (Seal) - Me First & The Gimmie Gimmies
"In The Ghetto" (Elvis) - some german punk band, I've forgotten the name of.
"Believe" (Cher Cover) - Duncan's Divas
"Rockafella Skank" (Fat Boy Slim) - Snuff
"Your Love" (The outfield) - Less Than Jake
"I Melt With You" (erm, I forget) - Good Riddance
"S.O.S." (ABBA) - Mad Caddies i think.
"99 Red Balloons" (Nena) - Goldfinger
Punk/Ska covers just bring back good memories of listening to them in the common room with my buddy nearly 10 years ago.
EDIT:
I forgot about Snuff's cover of "Sounds of the underground" (Girls Aloud) and Lars Frederikson & the Bastard's cover of "To Have, Have Not" (Billy Bragg)