So what you actually want is a process which can autonomously scan for candidate files and rename them by formula. With enough motivation, I reckon I could do it using a .bat to grab the directory listing, and a .awk to convert that into a one-time self-destructing rename .bat. Or somebody comfortable with "proper" coding could probably create a .exe to "just do it".It's something to run regularly, ideally as a scheduled task or tagged on to the end of my daily get_iplayer script. There would be new files to process every day.