I've also been wondering about options for non-A/C P-cars. There are some unusual 12-volt portable A/C and evaporative cooling units available (e.g. Swampy.net). Has anyone had the nerve to try one of these?
We've even had the nerve to put this kit together:
MPC (Multi-Purpose Cooling) is a mobile misting system for cooling hot parts. Could even be used to cool overheated bodies.
Sherwood Lee
http://www.seinesystems.com