What should this Game be?

I created a very, very simple prototype and wanted to see what you think this game should be.
The initial concept was a frog on a lillypad catching flies...once caught moves to new pad.
But I think it could be more...any suggestions most appreciated.

Game Controls with arrow keys move yellow box in proximity to the moving black box.
Use spacebar to execute the action. When you get the "fly" you move up.

http://dl.dropbox.com/u/27139109/FrogGame/WebPlayer/WebPlayer.html

 

Not really positive what it could be, it reminded me of fishing. Use your imagination, it has some potential to be original.