Rene, they happen every Thursday in a Prodigy chatroom, have been happening for a couple years as I understand it. I bought 5 chips just this evening.
While Prodigy Classic can still be considered "internet", it is firewalled access. You need to subscribe to it to access it. Michael Knapp runs the weekly chat session/live auction, and usually knows whats going on! <VBG> The Prodigy Classic BB is how I found out about this hobby. Darn near every "heavy hitter" as I'd call them, collectors, historians and dealers are there. The BBS is easy to use, simple to follow.