One of the games I really enjoyed seeing at the Ottawa International Games Conference was Office Attacks by Arctic Empire. At its core, Office Attacks is a pretty standard tower defense game, where players have to plant towers and upgrade them to fend off waves of incoming enemies before they reach the end of a maze. Office Attacks goes off the rails in two ways: for one, the premise is straight-up hilarious. You're battling off annoying co-workers to keep your stress meter low. Two, towers are user-generated by assembling various office supplies which are gathered throughout gameplay. Not only do those parts actively effect the tower's range, rate of fire, and cost, but you can also trade those parts away with friends through Facebook Connect.
For all of its tasty mechanics, the sheer goofiness of a lot of the towers is what got me. Gatling Pencil Sharpner? Yes, please. Follow Arctic Empire to see how the game's coming along.