Button to copy directory path of a folder?

I would like to know how to create a button on the Opus Tool bar that can copy the Path of a folder (and a file if not to hard) and load it into the clipboard ready for when you want to paste it. This would be very useful.

See Commands to copy selected filenames to the clipboard

I've found Clipboard COPYNAMES=path to be invaluable for copying the actual (vs. library) path a given file.