Two years ago I played Cannon Brawl at PAX Prime. I liked what I played so much I bought it and have since been waiting for it to hit 1.0. Since when I originally bought it till now Turtle Sandbox Games(the creators of Cannon Brawl) have ported it to Mac and Linux and added a lot of new features to it. If you are looking for a fun couch/internet co-op strategy game you can pick up and play with a friend you should checkout Cannon Brawl. Cannon Brawl also features a interesting story mode that is worth checking out too.

http://store.steampowered.com/app/230860/