brename is a tool for renaming batches of files based on their existing filenames. For example, you could turn something like “01. Track Name.mp3″ into “Artist - 01 - Track Name.mp3″. Tested on XP, should work on other versions of Windows, and will probably also work on other operating systems.
NB: It can be fiddly with slashes, so it’s probably best to use forward slashes wherever possible.