I would like to be invisible! I think it's the best super power ever!
It gives you a lot of freedom, you could go anywhere and listen to conversations without being noticed!
The ability to do anything I wanted: omnipotence, omnipresence and omniscience.
Telekinesis. Preferably telekinesis that extends to my body, so I can use it like a form of flying.
Invulnerability would be fun.
As with all of these types of threads, I'm going to say either:
Omnipotence, or the power to have whatever power I so wish for as long as I want and whenever I want.
As I discussed earlier, mind control has the advantages of teleportation. Make people do what you want, upgrade to first-class for free etc. Only difference is you would be a horrible person but that doesn't bother everyone.