Portal 2 "Couch Co-op"?

It has local Co-op on PS360, but I'm not sure about Steam.

portal 2 has splitscreen support

Native. Just gonna throw it out there as I always do in co-op threads, Lego games are awesome.

Yes it does! :D

Requires 2 controllers natively. To play with 1 player using a controller and the other using kbam you need to enable the console in the game and add this line "joy_remap_player_for_controller1 2" without quotation marks.

http://pcgamingwiki.com/wiki/Portal_2#Split_Screen_Co-op

Edit: For some reason the command in my post does not include the correct underscore _ marks. Just go to the link I posted to see the correctly displayed command.

I dont believe there's any need for the console commands anymore. It's just straight up local coop

It is great but don't play it with your wife if you don't want to ruin your marriage.

Try Rayman Origins

Any chance I could hijack this thread a little bit?
My gf and I played a lot of co-op recently and since we are no consolers we use keyboard&mouse all the time.
Reading here about Portal 2and Trine 2 it came to my mind that we could use some cheap 360 controllers :)
Soo.... anyone know about a source? :P It can be some chinese blender, too :P

You can play Portal 2 in local co-op mode, but you need two same controllers (two gamepads, or two keyboards). Rather you have to find mod that make you can do that. That's a little mistake, and that's why I didn't ever play co-op of my fav game.

You can never have enough coop PC games. :)

A few others we enjoy:

Castle Crashers (our 4yo daughter likes this one as well, as long as she gets to play the pink knight)
Legend of Dungeon
A Virus Named Tom
Sonic the Hedgehog 2 (albeit not as fun for player 2)
ToeJam & Earl