PrimeFile is a free utility that finds duplicate files on your Mac in just 3 clicks. Drag & drop as many folders as you wish and click SCAN. Within a minute the app will give a report with all duplicate files by categories: images, videos, music, archives, documents, and all other specific extensions. It's really easy to see how much space each file takes.

Disk Inspector is a disk scanning utility for Mac OS X. It scans any supported drive and generates a chart representing the file system usage.

Disk Inspector scans the disk file structure, analyzes the remaining space, and represents your files and folders with intuitive sunburst-like visuals. Bigger items are larger in the diagram, making it simple to find large files.

OmniOutliner Pro is a flexible program for creating, collecting, and organizing information. Give your creativity a kick start by using an application that's actually designed to help you think. It's like having an extra brain - one that doesn't keep losing the car keys.