I'm mostly a "daily bandana bath" person, too. One friend, though, drilled a bunch of holes into a spare Gatorade cap which he uses as a shower of sorts. If you carry a Gatorade bottle anyway, why not make it double/triple/etc. duty? Gatorade bottles are very tough, so they take a lot of abuse, including throwing over a branch to carry a food-hanging rope, or boiling water for a hot water bottle at one's feet.