I told you my library could be useful. Anyhow, Warden doesn't scan for ReadProcessMemory so you should be safe using this on live servers. What this does is draws a neat little map of all the objects in the area -- players, NPCs, herbs, nodes... and some less useful stuff.. signs, benches, etc. Should be pretty uncluttered out in the world though.
Quick map legend:
White = Players
Blue = NPCs
Yellow = Objects (nodes, signs)
Gray = Corpses