Braid.

Doom 2 is fun in coop.

just trying to waste time (life) away.

Serious sam series

Torchlight, MW2 single player, Portal, Braid, L4D2..

Just go to Steam and have a look around :)

Thanks everyone:)

Like I said in another thread, here are some cheap but fun games I've worked through recently (some sp, some mp):

Star Wars Dark Forces 1 (or infact any of them, but the first one is best by far) - sp
Evil Genius - sp
Portal - sp
Day of Defeat 1.3 - mp
Fallout 1+2 - sp

Any classic adventure game. I was giddy as a schoolgirl when i discovered that scumm runs on the iphone, and like a charm

WAT!
I had the same reaction reading your post! holy shit my workdays are so saved!

i always return to playing peggle when I'm really bored.
also, super mario world is never wrong. or some smw romhack version, if you don't wanna play the original for the 50th time.

Trine is cool

Would have bought it if they added coop. >:O

I've got trine, but aparently there's no co-op for pc or something, or not in the way I expected it to work.

Wich is a shame, because it would add more depth to the gameplay I think, tho the singleplayer is great anyway.

Titan Quest for co-op

the new AvP is pretty fun with a couple of mates.

Gears of war 1 was best coop experience for me since doom (havent played L4D tho)

Yeah I agree, gears of war is pretty cool :-D

Thanks everyone, tho sadly not all of my friends have steam so I can't play the 'steam required' games.

Talking about valve, I myself can recommend sven co-op.
Tho if you want to play it without steam you have to play it through a class a network I believe.. haven't found a way around that yet(Hamachi won't do).

isn't steam for free? ._.

What's that have to do with it?

a requirement tends to have something to do with whatever the underlying is

Well, if you want to know why my friends don't have steam, ask them:P

Duke Nukem 64