Just because I like contradicting myself, I will say, in contrast to my comment on the "asynchronous" idea, that this might be a good "sometimes" option. I've been playing around with videoconferencing software, particularly ooVoo, which supports multi-user video conferencing (unlike skype) and is cross-platform (mac and pc). It's not a perfect solution, but it is certainly a good start. I'd be interested to have other folks look at it and tell me what they think.