Check out this excellent story about a family that decided to build their own solarhot water heater. The entire project cost about $160 in materials.
Now, it should be noted that the project was completed in Florida, and as such, the system has no way to make sure the pipes don't freeze, but I can't imagine that would be too difficult to design into this straight-forward system.
Brave New Leaf - Everyman Environmentalism http://www.bravenewleaf.com
posted 10 years ago
Another option is to use a black bucket (preferably the plastic gas container kind) hung above outdoor shower stall. Fill night previous, sun warms the black plastic rather rapidly, by mid-afternoon on a very sunney day water is nearly hot. On an overcast day, water is tepid - warm enough to shower in. Use a piece of surgical tubing or garden hose for the shower nozzle or rig to a sprayer you made yoursaaelf. No water pressure but gravity does just as well.