Alternatives to Google Helpouts?

Google Helpouts looks promising, but the community does not look very developed or specifically focused on what I am looking for.

Are any startups tackling the hire-an-expert/tutor-by-the-hour space?

I would like to find a list of experts/teachers/mentors that can jump on skype or a hangout to tackle problems like: teaching the basics of bitcoin or going over a programming problem in python or explaining how to best harden OS X.