Currently using an old Core with a 5m RGB strip as mood/wakeup lighting.
Have connected the 4 outlets of an extension cord to a relay shield with a Core.
Bought a cheap 433MHz socket set (3+remote) for €10, which I can now control using a Photon and a 433MHz transmitter, currently controlling some lights, though I got it to keep the house lit over the holidays.
Also have a relay shield in the garage hooked up to the opener, since there wasn’t a manual button, and the only remote was starting to give.
Have some 433MHz door sensor laying around which I’ve yet to set up.
Have two ‘VoronoIoT lamps’, using internet buttons, standing next to the TV as mood lighting. One has a DHT22 for temperature and humidity as well.
No ‘real’ automation yet, other than IFTTT timers calling functions, and a homebridge integration, though I’d love to spend some more time on that to make it a bit more autonomous (presence detection for lighting, for starters).