By BUILDER Magazine Staff. Sketchup is a great tool for builders who want to explore designs with clients without having to have a full-fledged CAD program. It takes just a few minutes to get comfortable creating the kind of quick, exploratory design sketches that one would usually do on scrap paper. There are also great tools for power users: With enough practice, you can learn to do complete presentation drawings. (The company that makes it says it has been used for everything from multimillion dollar homes to office complexes.) Drawings can be saved as .dwg or .dxf files for use in most of the popular CAD programs. It's available from the Boulder, Colo.-based Sketch 3D. Cost: $495. You can download a trial copy from Sketch 3D's Web site (www.sketch3d.com), to try out.