Why would you want twins when you really only need one? I'm not talking about humans, of course! I'm talking about twin files.
Over time, your hard drive can build up duplicates of documents, pictures and other files. These "twins" take up valuable space, and can become confusing. This is especially true if the twin file has a different file name. You have no way of knowing it's a doppelganger!
Anti-Twin is a free download that searches for duplicate files based on a byte-for-byte file size comparison. In the case of pictures, it can search by comparing pixels.
It's a great way to track down and delete space-wasting doubles. Just install the program and select which folders you want to search. Once it finds duplicates, you can choose to delete them.
System: Windows XP, Vista, 7