SpaceSniffer is a freeWare (donations are welcomed) and portable tool application that lets you understand how folders and files are structured on your disks. By using a Treemap visualization layout, you have immediate perception of where big folders and files are situated on your devices.
D. Oberle, B. Berendt, A. Hotho, und J. Gonzalez. Advances in Web Intelligence, First International Atlantic Web Intelligence Conference, AWIC 2003, Madrid, Spain, May 5-6, 2003, Proceedings, Volume 2663 von Lecture Notes in Artificial Intelligence, Seite 142-154. Springer, (2003)