An 1873 5 barreled Nordenfelt gun is up for auction online at  This original gun was captured by the U.S. during the Spanish American War. The gun appears to be in Spanish 50/70 caliber.  The octagonal barrels are blued and there are internal parts missing.   Bidding starts at 10 grand USD, and there are 5 days left as of 4/25/10.

Update: This gun  sold for $20,000 USD

nordenfelt 5 barrelled gun