Simple, useful, and handmade. These are the kinds of projects the DIYosphere lives for.
From EvilMadScientist: "We said that it's simple, and it is: it's a brick wrapped in a piece of paper...hese are "cement bricks" -- red dyed cement-- and cost about $0.25 each. Wrapping them up keeps them from scratching up your shelves and books." These left-brainers chose some Psis and brackets for their physics texts, but the technique is simple and could be applied to anything!