Another simple, good idea.

We saw one of these earlier this year on a small sailboat.  An excellent addition.  This gives us pressure water for washing hands, salt water off your feet, rinsing dishes, dirt off the anchor line/chain.  When it is cool out (January here in Florida), it can be left out in the sun and gets pretty warm water.  Gail even used it to wash her hair. 

The simple stuff works.  Because it puts out an fine spray, under pressure, 2 gallons of water seems to last all 3 days of the weekend.