I have seen documentation of three commercial Z8000 systems; the Olivetti M20, the Zilog system 8000 (I think that was its name), and the Ithica DPS-8000 (I saw a Byte advert for it, not sure how well it sold). And there were as Dwight stated numerous commercial Z8000 S-100, multibus, STD bus processor cards (once again advertised in Byte). Lastly the Commodore C900, which only made it to evaluation machine stage. I believe that a few 100 were ever made, I just missed one on ebay a few months ago. I asked the purchaser a couple of times (through ebay) for his impressions and any information on it, but I got no reply.