ExOfficio Briefs work pretty well... although I actually prefer the longer length Boxer Briefs for walking, even in warm weather, as I find the length helps avoid unpleasant chaffing where you really don't want it when the going gets sweaty!
Perhaps not a household name, but certainly very visible if you pay any attention whatsoever to communications technology. (I don't work in the sector, I came across them when I was looking for a mobile internet dongle.)
I'm somewhat puzzled by the "new" Flex Vapour Rise Pull-on...
Given that my original Vapour Rise Lite Pull-on from 2 or 3 years ago features "Pertex Equilibrium outer fabric combined with a lightweight drop liner" and has "lightweight stretch panels at the side and under the arms" and weighs 250g for a size Large (Mens), just what exactly is there that's new, improved or lighter about the Flex?