ooVoo has many great features — from video calls with up to six people at once to video messaging to chat and file transfer capabilities. This could be possibilities to have mentors also far away, and for mentors to have more adepts at meeting the same time. Click the link for some of the highlighted features http://www.oovoo.com/
This is a recommendation from Krishna De (in the article «Ten tips for finding a mentor»), I have not yet had time to try it out.
Good luck and please come with feedback!