Have you ever found yourself low on disk space and wondered where it all went? Have you ever needed to make extra room but not known which files/folders were eating up the most storage? If you've ever been in one of these situations, you can appreciate the value of a graphical storage display utility like WinDirStat.
In a nutshell, this application will scan selected drives or folders on any medium (hard disk, removable, flash drive, optical disc, network drive, etc) and display a graphical representation of how much space is consumed by each folder and file. Each folder is represented by a rectangle which may be comprised of smaller rectangles that represent sub-folders. Files at the same level in the hierarchy are coded in the same color. By looking at the relative size (area) of each block, it becomes easy to see at a glance which files and folders are taking up the most space. Selecting a particular block will identify the folder or file that it represents in the top pane of the window, and from there you can take appropriate action -- delete the file, move it, open it to see its contents, and so forth.
Recently I was trying to determine why my laptop hard drive had gotten full, and WinDirStat helped me to quickly identify a directory full of temporary Zune video conversion files as the offending culprit. I also caught an ISO that I had created but not deleted which was taking up another chunk of space. I was able to recover about 30 GB of space in a matter of minutes. Doing the same task by clicking through folders and checking properties could have eaten up half an hour. The simple genius of showing the space representation graphically cannot be overstated.
WinDirStat is free to download and use, but they do accept donations to support the project. After using it a couple of times, I think you'll agree that its worth at least five dollars. And if you're a Mac user, check out GrandPerspective which does the same thing on computers running Mac OS.