I must confess that I am a soft touch for humour in design; that is why my personal favourite is the Bike Rack Birdhouse from Lauren Thomas and Jennifer Karam of Dimini , seen on TreeHugger here. The designers write:
The bikerack birdhouse mounts on the wall easily and securely offering a innovative indoor storage solution for your bike and helmut. Made of Mahogany plywood and finished by hand with all natural non-toxic beeswax and linseed oil, this piece will lighten the storage load and brighten your home.
Available for about C$ 200 from Dimini