Me: Hang on, you might be on to something... Super Smash Bros. Kart. THINK ABOUT IT.
Friend: ....MOTHER OF GOD :O
Yes, do think about this.
We decided that in addition to the normal Mario Kart powerups, each character should also have some special ability of their own but might require the player to have collected a certain number of coins to use. Like, Link can shoot swords if he's full up on coins, like he does in most of the games when he's full up on hearts. Bub and Bob shoot bubbles that slow down or temporarily trap other players. Samus's morph ball works kinda like a Bullet Bill. Ness and Lucas PK people off the road.
And Solid Snake's unlockable kart would, of course, simply be an overturned cardboard box scooting along the track.
DO THIS SHIT, NINTENDO
MAKE IT HAPEN