What is the best face/body paint brand that will not run off or smudge once it is on?

I would recommend looking at Temptu, http://www.temptu.com/ - they produce a special alcohol-based body paint for temporary tattoos that can last up to several days.





Alternatively, if you wish to use a water-based make-up product, this can be made more durable by using an anti-perspirant liquid on the skin before applying the make-up (to help stop sweating), and subsequently spraying on a special barrier spray on top of the make-up to prevent smudging. Mehron and Ben Nye are two manufacturers that I know of who make such a barrier spray.