I think Big Al wins in the ultralight backpacking division with his multi-purpose Aloe Vera gel.

I don't shave on trips as long as a week, but then I have a full beard. (Like many bearded men, I normally shave daily to maintain the contours of my beard.)

When I'm home, I shave with Mennen Afta gel aftershave. I like it because it's a good lubricant and it's water-soluble. The other lubricants I've tried always seem to leave an unwanted film.

Bear