For those who hate the math that goes along with figuring out arcs or curves when doing various types of small item carpentry work, Roler has that round covered. This silkscreened, laser-cut wheel-like device fits easily into a tool box, pocket, or for lady builders, a purse. Depending on one’s preference, the rolling ruler is available in increments of 12 inches when measuring in feet, 10 inches for inches only, or 25 centimeters for centimeters only. While it seems good for some curved surfaces, it could get tricky to measure more than a foot. For $8, backers get one product with an estimated delivery of December 2014.