Excellent little program, no doubt! What they has forgotten to say, in my humble opinion, is that it is also an interesting background generator; what I’m using now on my Amplify account is exactly a graphical representation of part of my hard disk 😉
GrandPerspective is a small utility application for Mac OS X that graphically shows the disk usage within a file system. It can help you to manage your disk, as you can easily spot which files and folders take up the most space. It uses a so called tree map for visualisation. Each file is shown as a rectangle with an area proportional to the file’s size. Files in the same folder appear together, but their placement is otherwise arbitrary.