A while back I pointed folks to SLAY Radio, all Commodore 64 remixes, all the time. If I may, I'd like to throw down some MP3 links to two remixes I particularily liked. Both of the original tunes are by Rob Hubbard:
The Sanxion theme, remixed by Peppy as a repetitive trance beat: right here.
The theme to One Man And His Droid, remixed by Marcel Donne as a Jean-Michel Jarré pastiche (this one is really good): right here.