A fairly accurate clone of the old arcage game Buster Brothers, also known as Pang.
In this game, it's your mission to destroy balls. Sound like fun? Well, hop aboard and get ready to have a blast! For another remake, also check out Pang'd.
The gameplay goes like this: There are bouncy balls terrorising the world and you need to spear them with your only-shooting-upwards harpoon gun. To complicate matters, the balls all have different methods of bouncing. Some bounce high, some low, some upside down, some just float around and some are heat-seekers.
The game is pretty close to the original, but loses points for having horrible collision detection which causes unfair death very easily. The standard ball also bounces only slightly above your head, making it difficult to dodge (especially when combined with other on-screen balls). But apart from that - if you can get used to those difficulties - I'm sure there's a decent game to be found.