A few I can think of
Mixu Paatelainen's header against Torino.............and Eoin Jess putting us 2 nil up at the Stadio Del Alpi in the early 90's (if only the referee blew full time after 25mins)
Beating Celtic 9-8 on penalties at Hampden in 1990, Irvine I think scored the winner after a class save by Theo - amazing
and more recently beating Rangers the last game of this season to stop them winning the league