I did these on my own years ago with civ2. I made a Midwestern map with the borders of states were coastlines. It spanned from MN south to AR, east to Tenn, up north thru MI and back to MN. I am not a modder, just like to make different maps. I tried to create canoes which were capable of river travel, covered wagon settlers with double movement and defense (circling the wagons) and just for fun I tried land and sea mines. The mines could be placed like listening posts, but invisible to foreigners until they occupy the tile and blow up. Nothing ever came of these ideas, but I did gain more respect for those that come up with the mods that work.
Take these ideas and run with them if you can for Civ4, I won't be trying to do them. I don't have the time, nor the know-how. Good luck, I'll be waiting!
