From Rafal Fraczek:
Duplicate Files Searcher (DFS) is an application for finding and deleting duplicated files on your computer It can also be used to calculate MD5 and SHA hashes. It is a platform-independent software and runs under Windows, Linux/Unix and MacOS. There are English, German and Polish language versions. Since DFS is entirely written in Java, it requires Java Runtime Environment Standard Edition (JRE SE) installed on your computer. The application gives a user some extra features such as manual files selection which gives a user the full control over files to be deleted, byte for byte files comparison (it ensures 100% accuracy), files preview, new user interface including results display, improved (faster) searching engine, several files comparison methods, Look and Feel adjustment and new report files format.