I found a program, wanting to find giant, useless files on my computer and deleting them to make space, but I found out, it also makes a cool little visualisation of all of the files on my drives.

Each square is a file.
The square's size, is it's file size.
The square's color, is it's file type.
This is showing all my 3 drives.
EDIT: The squares are sorted into drives, then into folders.
File types:
(there's hundreds more, but these are the biggest ones)Because of this program, I deleted a 110GB folder I never even knew existed.
Program usedShare your own, if you're bothered to wait.