Recommendations for system link co-op games

I have siblings and younger cousins that come over for some co-op fun on the 360. So far we’ve only played ODST and Left for Dead for 4 player co-ops. Sometimes I have more than 4 players and was wondering if you guys know any good 4+ player co-op games? I hear borderlands is good. It’d be nice to do CODMW2 but it only allows 1 person per xbox.

http://www.co-optimus.com/

Definitely useful.

Co-op games I recommend right now that me and a friend are all over right now that are great for co-op:

Army of Two
Army of Two 40th Day
Resident Evil 5
Splinter Cell Conviction (amazing co-op campaign)

Sadly those are only 2p co-op

At the moment the only 4p co-op I know is Lost Planet 2. I don’t now if you can split the screen 4 ways though.

Unless you’re looking at the 360 marketplace.

Doom
TMNT The Arcade Game
Turtles in Time Re-Shelled

Check that site out, it has them all + rating.
-McFly

Doom for the win.

Also, Gauntlet and Castle Crashers have four player co-op on a single screen.

Castle Crashers FTW! XD