Gee, I honestly don't remember....
I know it was one of the mirrors listed on <a href="
http://www.mythguide.org/demos/mythiii/" target="_blank">this page</a>.
As for which one, I don't know.
Also, playing this demo reminded me exactly how much I suck at the Myth games... I still haven't managed to win the demo level. :eek:
I just reinstalled Myth II and this demo looks AWESOME in comparison. The units use polygons now instead of sprites(?). Anyway, they look tons better, especially when zoomed in a bunch.
Also, in the options pane of the demo, there is an option to use ATi TruForm. If the Radeon 8500 comes to the Mac soon, this could be one impressive game indeed.
Anyway, good luck with the download. Oh, and as for the iMac 500 MHz... you'll definitely be on the low-end of the system requirements, but it will run. It's pretty jerky on my G4/500 DP w/ Radeon. Only slightly better on my Ti PB 667 (also with Radeon, of course). The GPU in your iMac might be a wee bit overwhelmed at high quality.
-Ender