I know I could [use AHK to bind keys](https://superuser.com/q/50705/34958) to bring a predefined window into focus, but I'm looking for a utility that will allow me to assign shortcut keys on-the-fly to bring a specific window into focus.

Ideally:

![enter image description here](https://i.stack.imgur.com/xvgiy.png)

Does anything like this exist?