Dolphin has a ability to rename multiple files by numbering them, though the functionality is currently limited and only useful in certain situations. One useful application would be renaming a set of photos.
Select the files you wish to rename, then right-click on one of them and select F2). You will be presented with a dialogue where you may specify what you want the files to be named.(keyboard shortcut
The '#' symbol anywhere within the file name will be replaced with a number, starting with '1' for the first file and continuing up for each file after that. Placing multiple hashes will add leading zeroes to the numbers.