From den4b Wiki
ReNamer is a very powerful and flexible file renaming tool.
ReNamer offers all the standard renaming procedures, including prefixes, suffixes, replacements, case changes, removing the content inside brackets, adding number sequences, changing file extensions, etc. Advanced users can program their own algorithm using Pascal Script rule.
ReNamer allows you to combine multiple renaming actions as a rule set, which can be saved, re-loaded, and edited. In addition, it can rename folders and process regular expressions. It can handle Unicode (non-English scripts).