One of my productivity aspirations (read: not a goal) is to get better at utilizing the keyboard for quickly completing or automating tasks. macOS has great support for keyboard shortcuts, and I've also been playing with Keyboard Maestro and PasteBot quite a bit lately.
One of the challenges of building shortcuts, though, is you start to run out of choices for your modifier keys. While working through David Sparks' Keyboard Maestro Field Guide recently, I discovered a reference to the Hyper key. The idea, introduced to Sparks by Brett Terpstra, is to use a third-party tool (such as Karabiner Elements) to map Shift-Control-Option-Command to the caps lock key. Pushing all four of those keys plus some other key to execute a shortcut is too cumbersome, but pushing CAPS+E to run a processing script, read by the system as ^⌥⇧⌘S, on my Explorations in Modern Math PreTeXt file is easy. And it's rare that I'd need to type more than 2-3 capital letters in a row, anyway.