Changes

[http://sketchup.google.com/ Google Sketchup] (Very popular and useful planner, and easy to learn. Helps aid builders visually with it's 3D detail. You can download tiles and house models [http://sketchup.google.com/3dwarehouse/cldetails?mid=2be414a114815b9ef9d5388d05b6f880 Here], which all credit is due to Tich.)

== Calculators ==