iShow Invisible... Shows and hides the invisible files via a repeating dialog box. After you have revealed the invisible files, simply move the Hide dialog box out of your way or press Command-H to send it to the background. Any open folders should remain open when you change the visibility. This makes it easier if you have several folders open and want to view the invisible files.
CEILING CAT An interesting idea, but I can't help thinking it would work much better as a custom Finder toggle, so you could just click once to show and again to hide without having to muck about with the extra pop-up. (Version 1.0)