I'm vegetarian, so I'm not defending this at all, but as I understand it, boiling kind of is the best way to kill a lobster quickly. A friend of mine had a roommate who thought otherwise and tried to decapitate one for dinner. I don't know their biology well, but there's something about lobsters' brains spanning the length of their body, so it wouldn't die. Just horribly suffering and bleeding everywhere with a knife through its body. Tossing it in boiling water should near instantly kill it. All the water inside their shell steams immediately.