Control your pellet stove! With the adafruit ESP8266 feather with a latching relay feather wing
This could be used to control anything with a relay really over MQTT.
Requires an mqtt broker that you can connect to.
Also needs a credentials.h file with WLAN_SSID, WLAN_PASS, SERVER, SERVER_PORT, MQTT_USER, and MQTT_PASS defined in it.