Run a command by pushing the pointer into a corner

Go to System Settings → Desktop & Dock, scroll down to the Mission Control section and click Hot Corners. You get a pop-up menu for each corner of the screen: pick an action — Notification Centre, Apps, Lock Screen, Quick Note and others — and it fires whenever the pointer reaches that corner.

That is also why people end up hating hot corners. The corner reacts whether you meant it or not, and the bottom right comes set to Quick Note, so half the notes in your library were created by someone aiming at a scroll bar.

The fix is hiding in plain sight. While the pop-up menu is open, hold ⌘ — or ⌥, ⌃, ⇧, or several at once — and choose the action. That corner then only responds while those keys are held down. A deliberate gesture instead of a trap.