I solved the parallel and serial port problem in my observatory by buying one of these
http://cgi.ebay.com.au/ws/eBayISAPI....=STRK:MEWNX:IT
My old computer was becoming unreliable so I had to replace it. New computers have the problem of no ports.
This one worked perfectly and runs my parallel port camera and the serial port connection to the mount. It could be run wirelessly as well but I like sitting in my observatory.