I don't have one of these at the Shed of Reality, it's just a few steps to my own back door and a nice warm bathroom, but I lived with an outhouse for 7 years on our farm, and we have one at our old cabin where running a water or sewer line was not an option.
We've had vandals, wildlife, falling tree limbs and more in the 20+ years since I built this little backhouse--it just recently got a new roof, and Joseph seems to have solved the wildlife problem...
Sometimes a shed needs a shed, too...
So it was fun to run across this link on the Shedworking blog!
http://www.shedworking.co.uk/search/label/Thursday%20Outhouses