Under a $1 shelf brackets. These made out of what looks like 1 inch plywood. The design is pretty simple and you could even modify it to be prettier…if you have a CNC/shopbot to make them on.
http://www.instructables.com/files/deriv/FGS/RNL0/HFD18KPA/FGSRNL0HFD18KPA.LARGE.jpg
