This is a game I made in Java for my high school capstone project a while back, which I recently converted to Actionscript. I don't know if I even need to say this, but don't grade based on filesize; This is almost purely actionscript.
You are the green blob that starts in the middle. move over the smaller blobs to eat them and grow, and avoid the ones larger than you, which will eat you. Sort of like that fish game. When your blob becomes hollow, move to the edge of the screen to go to the next level.