Man last night I was playing MM and go all the multiballs lit and couldn't get the ball to stick in that Merlin hole (popped out like four times!) so I haven't ever got that multiball with all of them lit. Guess that'd be one - but that's so minor. Maybe more like owning Iron Man, Big Lebowski and traveling and competing in tourneys all over the world would be on my pinball bucket list.
If I could magically know how to fix any machine that'd be nice too.