Quick measure [C] For your next farm project, purchase only the materials you need when you use the ProjectCalc from Calculated Industries. The calculator tallies up exactly how much concrete, gravel, lumber, shingles, fence posts, bricks and other materials you need in linear and cubic formats. For example, to pour a concrete slab in front of the machine shop, simply measure the area and key it into the calculator using the "cement" button; the total is the amount of product you'll need to complete the job. Price: $25. Contact Calculated Industries, Dept. FIN, 4840 Hytech Dr., Carson City, NV 89706, 800/854-8075.