I have killed racoons that would not stop taking my chickens, but seriously? Vengeance? Naw. Just keeping my food supply intact. Keeping the critters out is the better way to go, and I've been redoing my pens with that goal in mind. I also had a problem with rats getting into the feed storage, then running under a nearby house. Not good! I relocated my hound dog out there, and the problem stopped. She didn't eat them, they were smart enough to find another source of food (and hopefully, shelter - ick).
We should try to live with predators, instead of attempting to kill them. That philosophy has shown to be a slide down the slippery slope of complete eradication, something I'm sure no one wants. To that end, beef up your pens and coops, and look into the netting - that's an interesting idea!