Using the Batch File Rename is easy and flexible. The program acts as a droplet, which saves you the step of launching the program and adding files. To use the Batch File Rename program the first time, simply drag and drop the files that you want to rename onto the BFR app icon. You have a number of rename options: Add Prefix, Add Suffix, Rename Files according to a list, Replace Text, Trim Characters from Start or end, Serialize, replace entire name, change case, and undo!
This app requires the fewest steps of any rename app because it is a droplet. Skip the clicks and looking around for your files in an "open file" dialog. Just drag your files onto the app icon, and go. No other rename app has an undo feature. This app lets you go back one renaming step to the previous name if you have that feature turned on (previous name is stored in the files comments).