Pretty cool
I got 112 on my first try :o)
Cool game. Only real problem I had, is once it got filled with babies and starting lagging a bit, I couldn't seem to make the surprise attack work... the babies ran as soon as I started to pop out, and got out of range.
When it starts getting loaded with babies, drop into your box and run to one side of the screen. Wait for them all to cluster on one side of you (your score will sink but don't worry about it) and then pop out and start killing! They always move away from you, so you can chase them back and forth across the screen picking them off, and just get in front of them before the reach the other side, and chase them back. And then drop back down into your box when it gets too crowded.