ps regexrenamer download at
http://regexrenamer.sourceforge.net/
RegexRenamer is a powerful but simple user-friendly graphical tool used to batch rename files using regular expressions. A regular expression (or regex) is simply text that contains special characters that together defines a pattern that can be used to match text, in this case filenames. Using the power of regexes it becomes easy to apply complex transformations to large groups of files that otherwise would not be possible with plain match & replace.