Moleskinsoft Clone Remover is an ideal application to easily perform this task. The program scans the system looking for identical files.
The scan set-up process is presented through a wizard, in which you can select which folders or hard disks that you want it to analyze and search for similar files.
After a few minutes, the program will display a list of all the duplicated files that it found, even if they have a different name. Any of these files can be deleted, moved, or copied to another folder.
Also, to be even more helpful, in the case of images, the program will display a thumbnail, so that the user does not have to open the files in an external viewer.
Trial version deletes only 20 files.