1. I'd do genetic research on how to improve humans. Increased strength, speed, you know the super soldier types. Maybe we can genetically engineer a 4 armed human to handle more weapons?
2. Fountain of youth and everlasting life. We all want to live forever!
3. Bring back the dead. Since everyone of us misses a loved one or two.
4. Remove part of the brain that handles pain and emotion? Enlarge part of the brain responsible for processing information.
What's your experiment?