If you have a dual monitor configuration for your Windows PC, then you can have some fun with the screenRelayer tool. It is an open-source free tool that can relay the contents of your primary screen in a flipped mirror state. It is as if you are looking at your screen in a mirror.
When you launch screenRelayer on a single monitor PC, then the window of screenRelayer application just shows repeated screen contents in a cascaded manner. But if you connect the second monitor, then you can send the screenRelayer window to the second monitor where it shows the contents of the first monitor in a mirrored state.
In order to make screenRelayer work properly, your dual monitor system should be correctly configured. For this, we have to attache the secondary monitor and then open Windows settings. In the settings, we have to open the System section and then the Display section. From here, we can choose the secondary monitor in the extended mode. Do not choose to duplicate the primary screen or display only any one of the screen.
Only after the proper Windows display settings, you should launch the screenRelayer application and then drag its window to the secondary screen. You can maximize the window of screenRelayer, but if you double-click on the screenRelayer window, it will switch to the full-screen mode. If you double-click again, then it will go back to the normal mode.
screenRelayer is one of those applications that can be used only for fun. Looking at the source code of screenRelayer available on GitHub, it looks like someone was having fun learning the basics of Qt framework which is used to create cross-platform GUI applications for Windows, Linux, macOS, Android and others. Beginners are going to find its source code interesting.
You can download screenRelayer from https://github.com/Braised-Lamb/screenRelayer.