Recommend Métamorphose File -n- Folder Renamer 0.3.0

Métamorphose File -n- Folder Renamer is a free, open source mass renaming program that combines great flexability with an intuitive interface.

Allows most command line renaming operations in a single utility, perfect for those of us that need to rename large numbers of files and/or folders on a regular basis.
However, the ease of the interface ensures a one-time user (I need to rename 5 gigs of mp3's) will not find it frustrating to use.

Main Features:
* Renames files and folders at the same time.
* Preview every item to be renamed before comiting changes.
* Load all files in directory and in subdirectories (recursive renaming).
* Undo renaming operation in case of mistakes.
* Save all program settings to file for later use!
* Renaming operations:
1. Prefix
2. Suffix
3. Set file extension.
4. Replacement or modification by: Character, position, or regular expression.
5. Insertion by: Position or every (number) characters.
6. Length modifications (padding, truncating, or both).
* Renaming styles: combination of: user text, numbering, id3 tags, date, time.
* Modifications: UPPERCASE, lowercase, Capitalize first, Title Style, sWAP cASE, 'DoRkIfY'
* Sequential numbering (enumerating) options:
1. Use integers, alphabetical, or roman numerals
2. Pad with any valid character to any width.(integers only)
3. Control step size, starting number, reset count.
* Rename MP3 files according to their ID3 tags.
* Set date and time manually or get from system.
* Use supplied defaults or specify your own date and time formats.
* Modular design allows great flexability and control, while keeping the easy stuff simple.