File management software/duplicate files

Are there any good utilities out there, either free or commercial, that will scan a hard disk and catalog (with hopefully the option to purge) redunant files? Or some general directory management solution that will help me figure out what all this junk on my hard drive is? Thanks in advance.

Like this-> Space Hound?

That looks good, I’ll check it out. I’m just curious as to what people here have had experience with.