This program came to my attention the other day. I personally am not into it but it is kinda' neat re the colorful way your entire HDD is presented. And if you've not seen it, you may find it more useful than I. I made a screenshot of the neat display of my HDD with the program--in its many rectangles and vivid colors. It's a quick download, it's free and installs readily. Play with it, find out more of what it does; it's just neat!
Here's what it does:
WinDirStat reads the whole directory tree once and then presents it in three useful views:
* The directory list, which resembles the tree view of the Windows Explorer but is sorted by file/subtree size,
* The treemap, which shows the whole contents of the directory tree straight away,
* The extension list, which serves as a legend and shows statistics about the file types.
The url is http://windirstat.info