There have been several cases at both college and professional
level over the years of goalies scoring on empty nets.  Of course
its rare and, unfortunately, no records are kept so recalling such
incidents depends on memory.  The only case I know of (and at the
time reportedly the only case ever) of a goalie scoring on a
DEFENDED net was Jim Tortorella's goal in the RPI Christmas
tournament around 1978.  Now that's a rarity!