Windows Directory Statistics [WindirStat]
Excellent utility to see what is taking up space on your hard drives.
Darik's Boot and Nuke
An iso file you can burn to disk, and then when you boot your computer from disk, you can run this Linux program that will let you nuke (erase/delete) all of the data on your hard drive for a fresh install of your operating system. Includes multiple passes and algorithmic methods to obfuscate data on the hard drive.
HTTrack Website Copier
Allows you to copy/download an entire website. It crawls each page individually.