Whilst watching some roadracing last weekend there was a stall selling "storage bags" for bikes, a huge heavy gauge plastic bag. You wheel your bike in gather the neck of the bag together and connect it to a valve that you connect your vacuum cleaner to and suck out all the air therefor keeping the bike in a stable dry environment.
One of those ideas that is ..... a bit eeermm.... not sure really but it could work in theory as long as you've drained fluids!!
