Mario and Luigi is awesome!
 

This is quickly becoming one of my favorite RPGs. The game plays like Super Mario Bros. (platformer) mixed with Super Mario RPG. PLus, it's pretty damn funny too. I highly recommend getting this one. If you have the GB player for the cube, it supports rumble as well.

I agree this game is pretty cool. I find myself laughing at the characters, especially Luigi's "Oh yeah!"

I do think the game is a bit too linear, as far as the story goes. I wish there were more sidequests and things of that nature.