Use drawer slides; mount the drawer on the wall; attach the shell to the slides, so it pulls out. Shifty Desk / Hallway Stand by Daniel Schofield This is such a great storage idea! It can be a shelf and a drawer.
Everyone might find himself in emergency situation under water somehow, what's better than wearing a life ring on wrist? Once you pull the bracelet when you are in danger, the slim bracelet will rapidly expand to a life ring to keep you afloat