Voivod (of course!) - Astronomy Domine (Pink Floyd)
Exhorder - Into The Void (Black Sabbath)
Anthrax - Cowboy Song (Thin Lizzy)
Therion - Summernight City (ABBA)
Napalm Death - Low Life (Cryptic Slaughter)
Anyhow, that's at least 5 of them off the top of my head. Couldn't find a video for Wrathchild America's version of Pink Floyd's "Time", which is probably favorite cover tune ever.