Killer Crates is an up-to 4 player multiplayer split-screen FPS type game. It's a very simple setup: Each player controls a crate, among lots of identical inanimate crates, and must try and identify the other players (the ones who are moving). If a player doesn't move for 10 seconds, their crate will automatically jump.
One player can use the mouse, the others use gamepads. Warning: this game was tested on children.
Downloadable (free) at http://gamejolt.com/games/killercrates/270149