Nest 1st gen and 2nd gen thermostats no longer supported from Oct 25

Is there a list of devices which have been rescued or extended by open-source software?

Lyrion Music Server (formerly Logitech Media Server) is open-source server software for Squeezebox audio players, https://lyrion.org/

Tasmota is open-source firmware for ESP8266 and ESP32-based devices, https://templates.blakadder.com/preflashed-stand.html & https://github.com/tasmota

Some IP cameras have open firmware replacements.

Some Chromebooks are supported by mainline Linux.

you can buy these sensors off aliexpress cheap