1) I must have lots - I can only think of a couple for the moment. We have a vertical cupboard that is inclined to open when we go round the bend. Especially if the tray attached to the door is full of wine bottles - as the tray appears to be designed for. Solved it with a door safety catch - the sort to keep babies out.
2) A van we saw on holiday had a large garage door that was hinged across the top. They had fixed rows of washing line across the width of the door to hang washing from while the door was open - brilliant.
3) We fill the fresh water tank with convential garden hose. Sometimes the pressure from the supply is so high the hose falls out. Another short (few inches) piece shoved in beside the filling hose holds the hose in place.
