I have this kinda ontop of my head but this is it:
The MULE is a robot vehicle used to carry weapons, ammo, medical tools, and other equipment. This is what ideas i have for it:
~the mule will carry medpacks, and ammo, to get it there will be two doors on the back, one with a red cross for medpacks and the other for ammo
~when a mule is spawned, to move, the first person to click it will be equiped with a remote (if he has a free inventory space) where ever on the map you click it will go excpt onto vertical places and in the middle of the air
~it should have a good amount of health
~cannot ride it
~emitters to show damage
picture:
http://news.cnet.com/8301-10784_3-9920456-7.html