the very first images i posted on this blog were of a stack of painted mdf i called my shelves. they were custom cut to fit into two wall recesses that essentially held them in place. i worried that my little physics based system might not work in another space, but i'm glad to say that they are working out nicely in our new home. it seems if they are wedged snugly into a corner, they are quite stable. i've placed the separate sections side-by side, floor to ceiling.