Getting to grips with the files and folders on your hard drive can be a chore, but the right tool makes it easier. WhatSize is a tool that combines the best of several disk visualisers into one package.
WhatSize scans your disk(s) and reports on the size of your files and folders with a straightforward, color coded, Finder-esque presentation. From there you can click through folders, drilling down to large problem areas, identifying files and folders was you go.