Using an ESP8266 ESP-01 module and an Arduino Pro Mini 3.3V I wirelessly update all outputs from my thermostat to here for data analysis and because it's cool. This requires a voltage divided rectifier since thermostats run at least 24 VAC RMS.
This sensor uses an ESP8266 Wireless chip directly connected to a DHT22. Its currently being tested for consistency and stability. The intention with this sensor is to be a low power sensor that I can run from a battery (I am planning to use a 18650).