Two Players, One Console, Cooperative Play?

boredme asks: "With the free time I'll have this summer, I thought I'd get in some quality couch-potato time. I'm married, no children, and our Playstation2 is nice because it can be both more interactive than TV and more social than a computer since it's in the living room. The problem is that the vast majority of two player games are sports or arena fighting games that only allow confrontational interaction; since I have a dozen extra years experience gaming, these competitive games get old very quickly for both of us. What suggestions for cooperative, (not online) multiplayer games do the Slashdot folks have?" Along a similar vein, the Gauntlet games (available for most platforms) offer similar opportunities for co-operative play, but no other titles come to mind right now. What co-op games do you have fun with that you can play using a single console?

"The perfect example of this is Baldur's Gate: Dark Alliance. The whole game, with storyline, can be played through with one or two players alike. Others, like Jedi Starfighter, are close as they offer a small set of two-player missions that are distinct from the one-player missions. (Googling for this, by the way, has turned up very short lists at best.)

I'm primarily interested in PS2 games, but I still want to know what XBOX, GameCube, or even PS1 or PC games in this category are available. I'd even like to hear about sports games that offer a cooperative mode, or games not yet released."