Some of the NASA Amigas were on eBay a year or two ago. That's not to say there aren't others they're still using, but I suspect NASA's Amiga era is over. 
Long, long over. I worked IT for Boeing at NASA (KSC) back in 2002 and was told that the Amigas had long since been removed from service.
(note however that NASA has Houston, Huntsville, Vandenberg and other locations where they might still have been in use)
