Foolish Games produces freeware arcade games inspired by the classics that ruled the arcades in the 80s and 90s.

Asteroid Defender is a retro style arcade shooter.  Destroy the asteroids while being on the look out for hostile UFOs. 

 
Instructions

Left Control - Missiles

Left Shift - Shields - watch that you don't overheat!

Arrow Keys - Thrust and rotate

Re-map keys they way you want under the options menu.  Run the game in full screen or window mode.

Asteroid Defender Source for BlitzMax

Asteroid Defender requires Windows 98, and DirectX 7 or greater

Check out  the following links for more free games.

http://www.free-games.com.au/ 

http://www.acid-play.com/search.php