Sting .v. Undertaker is an obvious one, as you've said
Sting .v. The Rock
Hulk Hogan .v. John Cena (with Cena as a heel)
Jake the Snake Roberts .v. Raven
Chris Benoit .v. Daniel Bryan
Mr Perfect .v. Chris Benoit
Sting .v. Ultimate Warrior
Steiner Brothers .v. Road Warriors
Sting .v. Shawn Michaels
nWo .v. Evolution
Evolution .v. Horsemen (Flair on Horsemen's side, HBK added to Evolution)
Bret Hart .v. Chris Benoit
Eddie Guerrero .v. Chris Jericho
Chris Jericho .v. Ravishing Rick Rude
Jake the Snake Roberts .v. Undertaker (done properly and evenly)
Stan Hansen .v. Vader
British Bulldogs .v. Chris Benoit and Chris Jericho
The Hardy Boys .v. The Rockers
....Just off the top of my head