I’m still typing this up, but check back soon for an article about using a Raspberry Pi 3, the amazing Home Assistant software, and a few other pieces of hardware and software to build a centralized home automation system. Home Assistant sets you up to run everything on the local network, so that your home automation still works without internet.
For extra fun, Snowboy, by Kitt.ai, gives you offline voice recognition, so that you can control things (lights, music, your TV, etc) with your voice.
I’ve had a lot of fun playing with all of this.