After a coworker screamed twice from this I made them a pretty RGB-LED display that flashes a rainbow when you press the button at the entrance to their cube. I am surprised I haven't seen any good products in this space. I feel like you could make good money selling programmers something that is essentially a button, battery LED and 6' of wire.
I’ve seen a product (forget the name) that does the opposite signalling. USB powered RGB light dongle on your desk/cube. Red means “don’t interrupt me unless the building is on fire”, orange was “don’t interrupt me” , green was “feel free to bug me with that question”
I’m sure they could be repurposed the way you suggest. But don’t most people in open spaces use slack or equivalent for that?
JWZ draped camouflage netting around his desk to make an ad-hoc "Tent of Doom": https://www.jwz.org/tent-of-doom/ . Maybe an actual tent would be even better.
Surrounding yourself by whiteboards might also allow you to approximate walls.
I had just replied to the comment above yours that doorbells do indeed have wires. Forgot completely about the new wireless ones. That makes much more sense.
