http://www.tetrisattack.net/ ?
Chain combos.. fierce competition-based Tetris. Super addictive-- most people (even mothers and siblings) are known to get hooked.. when jeepnut's slave said that, I immediatly thought Tetris Attack.
Well.. don't think I've played Dr. Mario/Tetris..
http://hallgames.com/store/videogame...Dr.-Mario.html
Looks fun.