We use a old traffic signal powered by a Raspberry Pi to similar effect. We have found it quite useful in providing timely feedback and encouraging the quick re

We use a old traffic signal powered by a Raspberry Pi to similar effect. We have found it quite useful in providing timely feedback and encouraging the quick resolution of issues. You can see pictures and source: https://github.com/tantalic/build-light https://github.com/tantalic/build-light