Private tutoring

I'm considering offering private tutoring, to teach others my various design and coding skills. I think there's a good market right now for people who need to learn new skills or change careers.

I live in New York City, so travel in the metropolitan area isn't an issue. I would use my own laptop, and hold tutoring in public places (until I get my office space).

Has anyone ever done this in the past? Do you charge the same rate as you would for creating work? What's in the highest demand?