Zombie Pwner
Just a Zombie killing game, stay alive as long as you can. You have unlimited ammo, and a single flash grenade.
Use the mouse to aim; fire with the left button and throw the flash grenade with the right.
Made for a friend, a very short project.
UPDATE: Added shotgun to game; you get another 10 shells for every 50 kills you get, and it is only available on Very Hard and OMFG difficulty. Also sped up gameplay a tad. The shotgun creates a moment of lag when fired, working on fixing this.
UPDATE 2: Tweaked shotgun - it now fires faster and can kill more zombies in a group. Made game modes more difficult, the most significant being Very Hard and OMFG (don't say I didn't warn you!). Also, added two options - the ability to choose the color of the zombies' blood, and whether or not their corpses disappear over time. Some other less significant tweaks as well.