From Davstar Apps:
Most cameras and media ripping software will leave your files with generic names that don't make any sense. Rename It! Pro allows you to batch rename any number of files and append it with text of your choosing. You can also index your files starting from any number you choose. Regular Expressions are now supported for trimming or manipulating your file names in any way you choose. If you already have the new names of your files in a text file, Rename It! Pro can add them to your file names. This can be especially useful when cataloging your TV shows and movies. Previews are shown if your files are images in order to assist with identifying your photo groups.