Hmmm...
An interesting idea which, if expanded on, could become quite an addictive and fun game to play. At the moment the game isn't great. Add a few add-on such as levels and power-up in order to make it a little more interesting. It could also do with some sound and music. As it stands, its below par. It gets boring very quickly. Improve it and you'll have a pretty good game which i'm sure many people will like.