Fun co-op games?

So me and my friends are playing some co-op games together but sadly we seem to have run out of games to play =(...

Do anyone know any good co-op games beside these ones:

Sanctum

Dungeon Defenders

Trine 2

Pref something along the ones i have listed above.

• Lego games
• Sport games
• Alien Swarm
• Spiral Knights
• Dungeon Defenders
• Killing Floor
• Left 4 Dead 2
• Portal 2

Serious Sam HD 1 & 2, and Serious Sam 3: BFE. These games are very much fun in coop.

SWAT 4. You will not regret it.

SWAT 4. You will not regret it.

Priapus101

Along your lines, Magicka and Lara croft guardian of the light(coop with 1 other player only).

Not the lines, Payday the heist(4 coop), Fear 3(1 other for mission and 4 coop for etc). My recommendation is left4dead 2, 4 coop zombie shooter, fast paced fun, thriving community and lotsa mod maps played.