Once every few weeks I run into a situation where I need to rename a lot of files. Operations like adding or removing a suffix or prefix, incremental numbering or find-replace of filenames. I have been able to do all these using the Bulk Rename Utility.
This tool is handy to have around for quick rename operations of all sorts. The UI looks intimidating, but you only need to use the sections in the bottom half that apply to the rename you want to do. For example, to find-replace substrings in filenames, you would use the 3rd section. All the actions are immediately visible in the upper window, with the changed filenames displayed in green. Only when you are satisfied with the changes, you can go ahead with the actual rename.
Tried with: Bulk Rename Utility 126.96.36.199