All joking aside, this could be interesting. It makes me think of that service that existed for a while where you could ask a question of a topic area, and it would send an IM to people and ask them to answer it. I forget what it was called, but I used it for a little while.
The payment/HIPAA compliance aspect are pretty interesting, too. I would easily throw $50 at a 10 minute consult with a doctor instead of having to make an appointment and haul myself in to the local clinic. Particularly if said doctor could then fax a prescription for something completely boring but still not OTC to my local pharmacy.