DUDE is a cross-platform GUI utility for finding duplicated files, delete or link them to save space.
Features:

• Scanning for duplicate files in multiple designated folders (up to 8). Optional “Cross paths” display mode
• Optional command line parameters to start scanning immediately or integrate Dude with your favorite file manager
• Two synchronized panels: groups of duplicates and directory of selected file
• Two stage processing: interactive marking of files with multiple criteria and taking action on marked files (Move to Trash/Recycle Bin, delete, hard-link, soft-link, create windows .lnk shortcut file)
• Support for regular expressions or glob expressions syntax
• Searching for duplicates based on the hash of the file content. Different filenames or extensions do not affect the search results
• Works on Linux and Windows