Great topic!
1) Tecmo NBA Basketball
2) Bubble Bobble
3) Tecmo Super Bowl
4) Super Mario 3
5) 190 in 1 (Japan game that had 190 games in one cartridge- about half of them were "Game Genie" versions of games and half of the remaining were weird games that I wasn't sure of the point, but the rest were very playable, fun games- this may be like being granted 3 wishes and wishing for 100 more, but it was all on one cartridge, so I think it counts).
6th man is: Anticipation (yeah, I know I'm lame)
As for the Super Mario Galaxy comment, I spent every available minute I had getting each of the 120 stars when it first came out. I never thought there would be a game as good as Super Mario 64, but this one comes darn close...