Pickard Iconic just turned me on to Ultra-Ever Dry, a material they advise will 'completely repel almost any liquid'. Watching the video one can believe it. Ultra-Ever Dry is produced by Global Industrial. According to their description, it is a "... superhydrophobic (water) and oleophobic (hydrocarbons) coating..." The video displays most obviously industrial applications, but one can certainly envision a host of uses in the tactical industry, from the outside of a grunt's ruck to - imagine it - the outside of a poncho liner (cue heavenly music and a light spearing down from on high).
Further description as follows: "Ultra-Ever Dry uses proprietary nanotechnology to coat an object and create a barrier of air on its surface. This barrier repels water, oil and other liquids unlike any coating seen before. The other breakthrough associated with Ultra-Ever Dry is the superior coating adherence and abrasion resistance allowing it to be used in all kinds of applications where durability is required. Ideal for use on metals, plastics, wood and fabric. Quart can covers 42 square feet."
Watch the video then comment. What sort of practical uses do you see? It obviously doesn't breathe, so it wouldn't work well on boots, but what about the exterior of communications kit headed for the field? Sound off if you care to.