Stumbled across this while looking for something else. It's the interwebs, so it could be a lot of made up stuff, but shutup it's interesting anyway!
My favourite has to be the 1917-18 change where they started letting goalies fall to the ice to make saves. Can you imagine what goaltending would look like these days without that?
My second favourite is the 1950-51 change which seems to imply that a backup goalie could play for the opposing team. Won't you join me in picturing Brent Johnson playing (abismally) in the Islanders' net just after knocking DiPietro's smile off his face. Okay, that doesn't quite make sense, so instead let's picture Marc-Andre Fleury doing jumping jacks in the Islanders' net just after Brent Johnson knocked DiPietro to the ground.