I've just posted this over on the Ultra thread, but this is probably the more logical place.
There's a free Windows remake of Archon, and it can be found at
http://archon.curvenet.co.uk
I much prefer the original game to Archon Ultra. I liked the added attack mode, but I felt the battles were too sluggish in Ultra. The remake is very accurate, and matches the game speed exactly (I'm so geeky that I ran them side by side).