Mental ventriloquism. I want to be able to 'throw my thoughts,' so that they seem to be coming from someone else. It's different from 'Incepting' people or whatever, because the idea wouldn't [i]need[/i] to take hold -- it would just be echoes of my own consciousness. Illusions of ideas. They don't have to last (if they did, that would make the world feel pretty empty -- I don't want to control people, I simply want to be able to trick them on a mental level. 

Yes, it's a supervillain power, I'm okay with that. I'd use it for mischief, and to 'open doors' to people that piss me off (wanna know where Al Qaeda is hiding? Put MDK on the phone with a terrorist, problem solved!) Eventually someone would try to weaponize me, and I would have to start using my power to protect myself (and by extension, the world, from an abuse of my own powers by a less scrupulous party).