Rename multiple files ( it is not a Registry tweak though. I thought this to be really cool, so I have put it here)

A new, small, neat feature for Windows XP deals with renaming files. I personally have always wanted the OS to include a way to do a mass file renaming on a bunch of files. You can now rename multiple files at once .Its really simple:

Select several files in Explorer, press F2 and rename one of those files to something else. All the selected files get renamed to the new file name (plus a number added to the end). Simple J

source:here