There's a good rule of thumb for adventure: If you're squeaky clean, you're probably doing it wrong. Mud, sweat and various other methods of sullying one's clothes and body seem to come with the territory. That said, it's always nice to freshen up a bit, whether you're prepping to re-enter civilisation, or have simply been wearing the same t-shirt for six days in a row.
While giving your clothes a rinse in a spring-fed mountain stream is a tried and true option, if you want a slightly more thorough cleaning, there's now an method that doesn't include lugging around a hill-billy style washboard: The Scrubba.
The Scrubba is a soft-sided, waterproof bag with an internal, lightweight, bendable washboard. Toss in the offending objects, add water and some eco-friendly detergent, then give it a solid shake, rubbing the clothes against the grating. 1 minute of scrubbing will have you feeling fresh, or three minutes for highly-soiled items. Remove your items, and hang 'em up to dry. Fresh socks and underwear forever! (Or at least until you run out of soap.)
The Scrubba Wash Bag
Retail price: $65 USD