Leisure Quip 12V Turbo camping shower

While this is mainly a camping shower it has any number of other uses. It comprises a submersible pump that simply plugs into your cigarette lighter, a length of water pipe, an on/off switch to the pump and a shower head that has a suction cup (for attaching to flat surfaces) and a S-hook so it can be hung from a convenient tree branch. The water flow is adjustable and the whole kit fits in a handy carry bag.

For the technically minded the pump only draws 1.5 amps, which will hardly make a dent in an ordinary car battery; when used within reason of course.