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.
This project is not for the average DIYer as it requires access to a CNC machine to cut the pattern in the ply. But if you have a very good hand and an equally good jigsaw you should have no difficult (Diy Furniture Building)