Definitely one of the best tools to rename a lot of files. Perfect for renaming mp3 files and others. Often used functions (deleting double spaces/replacing underscores etc) are built-in, Immediately see changes, What you see is what you get, UNDO, At-a-glance-display, special functions for Inserting/Replacing, special functions for changing case, Numbering/Renumbering (decimal/ hexadecimal/ octal/ latin/ excel) with BIG numbers, shorten filenames to 64 chars for CD-Rs, Swapping of parts within the filename, Enhanced sort function (sorting by file length, sorting FIRST by extension THEN by name...), Immediate problems check, check for compatibility in other Operating systems (DOS, Mac, ISO 9660), Insert Startrek STARDATE into the filename. Has 2 modes: Basic Mode for the standard functions and Expert Mode for the advanced user.