360 Co-op play, side by side, not online

[woodguy]

All,

I've searched online, and searched here, but I still can't come up with a good list of quality co-op side by side games for the 360.

My buddy and I like to get together, smoke a little green and play co-op games.

Our favorite by far is Rainbow 6 Vegas, nothing even comes close including Halo 3.

So, I ask you all to help me out with your favorites.

What do you like?

Thanks,
Woodguy