Another idea I’ve been playing with is to use a Chrome device as a simple Eddystone beacon to broadcast a url to local devices.
I found this post by Francois Beaufort describing how to get it running with a link to some source code too:
After a bit of playing (and remembering to enable the chrome://flags/#enable-ble-advertising-in-apps flag , oops) I have managed to get my Chromebook to broadcast a url over Bluetooth Low Energy!
The next step will be to try to build this into a Kiosk application for a Chromebit. Could be useful for digital signage in shops or in the office for locating meeting rooms etc I suppose.