Google has released a very cool tool called SketchUp.  The tool allows you to build three dimensional models that can be to scale. The models can be quickly worked up using a variety of tools like the rectangle, circle, arch, push pull, rotate, and orbit. You can then fill in planes with colours or with textures. SketchUp is a desktop app and proves that Google can, quite successfully, write software for the desktop.  It will be interesting to see what happens as the company moves off the Internet onto our desktops more and more.