In the anime Code Geass...
Lelouch vi Britannia is a young man who obtains a power known as Geass. There are multiple forms of Geass present, and owned by many characters in the story, but we'll only be focusing on the one Lelouch has.
Lelouche's Geass is one of control & command, similar to hypnotism. Here's it's abilities and restrictions:
When making eye contact, the user can command someone to perform any task or request.
The person who is under the influence of Geass is not aware of their actions pertaining to the requested task.
Once used, the Geass will not have effect on a person for a second time (i.e. The Geass can only be used once per person).
Requests should not be impossible (i.e. "Fly away into the sky" wouldn't work).
What would you do with this power?