SequoiaView disk viewer

A nifty way to view disk space used by files.A description taken from their help file-We horizontally subdivide all available screen space into rectangles, with the size of each rectangle being proportional to the size of the files and directories at the highest level in the hierarchy. So if a directory is taking up 50% of disk space, the rectangle representing this directory will take up half of the available screen space.

The resulting rectangles are then subdivided in a vertical manner, proportional to the sizes of files and subdirectories in the directory the rectangle represents. This process is repeated, alternating the direction of subdivision per level, until all files are represented by a rectangle.This link-
http://www.win.tue.nl/sequoiaview/