Collector's know how rare this event is, just like the TI-99/8 prototypes mentioned a few months back, the Entex AdventureVision (Adventure Vision) is available on eBay with several additional games: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260032965438

This is one of the rarest videogame systems ever, mostly due to a quick entry and exit from the market and the fragility of the rotating mirror-based display. I put a bid in, but just for fun. Expect this setup to quickly surpass quadruple digits...

Here's a good site with AdventureVision information, who I'll be working with for that particular section in my forthcoming home videogame and computer history book: http://www.adventurevision.com/ (yes, despite my aggressive collecting, this is one of the few systems I can pretty much guarantee I'll never own...)