Mh,
Focused on Console, or also Computer Games?
Mario Brothers (see above) and Joust (also a one screen platformer with a similiar gameplay to mario brothers)
I've just played DynaBlasters on the Amiga (5 Players: it included an adapter for 2 joysticks over the paralellport in addition to the "basic" two + one player on the keyboard), so I cannot comment on the number of players for it (or bomberman as it was called outside europe afaik) on different systems.
and also: Stunt Car Racer on the Amiga - it was the first "racing game" (2 player via Nullmodem Cable) where I actually felt the "dives" in my stomach. And staying with racing games: Lotus 2 Turbo Challenge on the Amiga (and ST?) did not only allowed for 2 players via split screen, but also a Nullmodemconnection, so that 4 player could race against each other :D
