I want to introduce a new enclosure project for the Pi Zero. It's a new din rail housing and protoboard with integrated voltage regulator.
that was exactely the idea behind this enclosure set. You can integrate other ciruits or boards together with a Pi_Zero (W) on a din rail.... Here another example with a Homematic IO-Module for the Homematic wireless automation system (very popular in Germany): The module represents 4 buttons with 2 rockers. IT's easy to control the "rockers" via the GPIOs of the Pi-Zero...
Interesting the integration of the two boards. In a general view, IMHO, the interesting aspect is that this can be considered also a good prototyping platform. Is possible to provide the rail base supporting the PI-Zero with custom PCB ? I think that an option of this kind opens a lot of possibilities for derived specific products for industrial or home automation.