Curse of the Mountain Man
A downloadable game for Windows
This is my submission for the Giant Bomb Game Jam. It's pretty accessible though. Dual stick shooter. Keyboard compatible if you don't have a controller hooked up. Done in Game Maker: Studio.
Download and run the executable in Windows. It should need anything else. I tested it (maybe three times...) with an Xbox 360 controller which worked great, but you can also use the keyboard, though you will run into that annoying problem where you can't press more than two or three keys at the same time.
Dunno about system requirements, but it runs fine on my dual core with a GTX 550Ti and 4 gigs of ram.