#5: Echoes

Combine Asteroids, Geometry Wars and some game involving shields and this is basically what you get. You control your ship using the mouse, and the ship is constantly shooting in one direction. You can change which direction the ship is shooting by tapping the respective WASD buttons.

Giant meteors are hurtling at your ship constantly, and as in Asteroids, bigger ones break into smaller ones after you shoot them. As you progress, eventually little blue enemies and waves of black holes, red ships in snake-like formations, and gigantic blue enemies rain down on you like heart conditions after a hotdog eating contest. You don’t have lives or bombs, but a health bar and a shield surrounding your ship that gets smaller with successive hits, eventually resulting in your horrible, flaming death. I know, it sounds like a blast of fun and excitement! And it is!

Pros:
Just as fun as Geometry Wars, arguably
Fun graphics and special effects
Good variety of modes
Small download size

Cons:
May make your eyes bleed
Extremely long start-up time when loading the game