This is a duplicate file finder with a customisable range of ways to search out redundant duplicate files. It's especially good at handling the files once found.
We put it to work on a heavily used PowerBook G4 with 64GB of files. In the first test it was told to look for any files with the same name, file type, extension, size and creator. In the second test it looked for duplicate files last modified on the same date. We set it to look at the whole local hard drive in our first search, then individual folders.
We were impressed by its speed and thoroughness, and by the range of options once it had found the files. Search results came back surprisingly quickly compared to other apps such as Allume's Spring Cleaning 8, listing items in the main panel and presenting us with a range of options. These were to hide, modify, delete, burn, move & copy, trash or export the returned items.
You select items by clicking them: C+click for multiples or by using one of three auto-selection buttons - Select all, Select one of each duplicate or Select all but one duplicate.
We trashed the duplicates and, hey presto, 3GB of duplicate files, everything from double-downloaded podcasts, double-ripped songs to iTunes and double uploaded photos from camera cards were gone.
This is one of the fastest ways to free up hard disk space we know of. Other tools do much the same task, but Spring Cleaning is slow, DupNuker has a really tedious interface, Mr Clean is a little too basic and Singular, which is a good all-rounder, has a poorer feature set. This may be a bit pricier, but otherwise gets two thumbs up.