A simple windows program that generates a rule-of-thirds overlay on your screen. This was created primarily to help people capturing video game footage for trailers.
Open up the application. You now have an overlay and a smaller window. When you close the smaller window it will close the overlay as well, but you can otherwise minimize, move, and hide the smaller window without affecting the overlay.
When recording a screen capture, make sure you are only recording the target window and not the screen. If you record the screen then the overlay will show up in your capture footage. Play with it until you figure out the right configuration for your setup before you commit to anything.