I once went three months without a real shower after a few hurricanes. I would wash under a large teapot, heated as necessary. It's unbelievable how good that can make one feel and it has some kind of cool effect on my hairstyle that I've never been able to replicate with plumbing. I'm definitely going to be drilling out a bottle cap tonight. Sometimes the best ideas are incredibly obvious.
"Every day is a new day to a better future"
"Of all the things that matter, that really and truly matter, working more efficiently and getting more done is not among them." ~ Mike Dooley
"What if I told you that you couldn't have anymore of anything... No more friends, no more money, no more anything, until you first got happy with what you have?"~ Mike Dooley
"The only true wisdom is in knowing you know nothing." ~ Socrates
I use the large-mouth Aquafina water bottles. They are light, I can fit my SteriPen in the opening, disposable, and 'squeezable'. A little practice and one or two fillings is all you need. Make the holes small; I think I used a 7/64" or 5/64" drill bit. Should be large enough that you can force water through it with a gentle squeeze, but small enough that it doesn't just come dumping out when you invert it. I like to let it sit in the sun for a little bit so that I don't make this face: when I start the 'shower'.