AVG Cleaner for Mac OS X is a simple to use hard drive clean up utility. It is made by the same company that develops AVG Antivirus.
AVG Cleaner consists of Disk Cleaner, and Duplicate Finder. Disk Cleaner allows you to clean cache files, logs, downloads and trash. Duplicate Finder looks for duplicate files inside your pictures, music, videos and documents folders by default, but you can also specify a custom folder location to search for duplicates.
AVG Cleaner is free and you can get it from App Store.