Here is my job for reading energy meter Landis & gyr by infrared Arduino and MySensors.
Work with arduino mega but i have one with software serial work on arduino uno, nano etc. the schematic is on github.
RS485 Gatway with relay and DS18B20 sensors
'Mysensor' a smoke detector with sound detection
DHT11 and Ethernet Gateway with enc28j60
RooDe - A "reliable" PeopleCounter
UV skin type sensor
flic.io -> homeautomation -> Garage Door node
Candle - 433 Hub - A universal 433Mhz signal cloner