You would want a map where the .map file does no special assignments of things like sites.
I have a bit of a write-up on map sizes vs number of players at
http://www.dom2minions.com/maps.shtml
You could also use one of the randomly generated tiny/small/medium maps for a tourney game. There would be no preplay advantage. They download quick. Might even be fun to say "You will be playing on tomorrows Small #4 so be sure to download it".
Or set something up to randomly create a map. Have the players download the .tga and keep the .map file on the machine that generates the game-start. The players dont even get a .map file to clean info from.
[ May 16, 2004, 14:52: Message edited by: Gandalf Parker ]