I've looked into this myself, especially since I tried some of the flavors that Dolfin chocolates is starting to import to the States. Earl Grey Tea chocolate, chocolate with ginger, chocolate with peppercorns. It seems like a cool idea.
I talked with the resident tribal chocolatier (is there any surprise that there's a resident tribal chocolatier? I didn't think so...) and he's been interested for a long time, but is still investigating the possibilities of a conching machine so as to make a professional level product. If pro-quality is less important than the process of going from bean to bar, then his opinion was difficult, but hardly impossible. I say go for it and invite me over when you have something to taste. :)