Sim Innovations’ Knobster* is on sale right now for €80 (normal price: €95) until 2 December. If you’re not familiar with it, there are two products called Air Manager and Air Player, where you can put a custom instrument panel on screen or on its own dedicated monitor. And then, you can click (or touch, if you have a touchscreen monitor) anything that rotates, like a COM or NAV standby frequency or your Kollsman window, and use the Knobster to dial in the correct number.
* No, not Monster, autocorrect. And not Lobster, either! 