I've implemeted a similar method to what Moonfisher suggested in Astronomo v2. It feeds of veggies by causing them to suicide all their energy in one giant shot which is (hopefully) directed at my bot. Sadly it doesn't work extremely well, and the veggie's body is wasted entirely, but the code causes havoc with other bots trying to feed off veggies, and it looks pretty silly too. And it leaves enough room for improvement in version 2.1...