Becoming a Vampire. I would live forever, have incressed strength, be able to fly, incressed reflexes, etc. And by living forever, I can incress my knowledge to super human inteligence. Then I can invent other things like what Packer said. The bad thing would be I couldn't go in the sun, play with wooden sticks, go near churches, have friends, and I would have to get used to drinking blood.
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ARG!