Good co-op campaign games?

What are some good co-op campaign games preferably shooter and online campaign thanks!

Gears of War 1/2, Halo 3, Resident Evil 5, Splinter Cell: Conviction, Left 4 Dead 1/2 (not exactly a campaign though) Operation Flashpoint: Dragon Rising is a bit of an acquired taste but I enjoyed it (MP and SP sucks though imo, co-op makes it good).

edit: Can't believe I forgot Borderlands.