Well I decided the other week to do my own geeky project to a wall that is pure gyprock - no studs, not support in the middle at all, so hanging a picture is impossible.
It's a large white wall, so I decided to do something truly geeky and make a feature wall using 140 pages of black and white Japanese comics. They were gently stuck to the wall with watered down PVA glue, and using a level I kept each page straight. Once dry, the wall was then sealed with matte spray varnish.