To make the automatic pepper mill, you only need three materials.
1) A drill (cordless) set between 150-500 rpm (if your rpm is set too high, the pepper grounds may come out too coarse)
2) A salt shaker/pepper mill
4) A saw
5 A tollerance for sneezing (not really)http://www.blackanddecker.com/ProductGuide/Product-Details.aspx?ProductID=6149
This link is of a cordless screwdriver that would be smaller and make this peppermill more compact. The only problem is that this screwdriver has no chuck to hold on to the peppermill, so it might need to be epoxied or glued on.