I think the area under your bed is awesome. It's the best place to store stuff you need/don't need or just want to hoard until the time comes when you need it.
I found this awesome idea in a storage book to build a storage unit for the bed. It didn't have any instructions but I decided to give it a go anyway. All I needed was some caster wheels, two wooden boards, screws, handles, lacquer and wall paper and there you go! Under bed storage unit thingies: