As a quick weekend project, I hacked a night light to turn on and off when you talk to it through Google Assistant.
I replaced the inside (which consisted of a simple LED, battery and switch) with a Particle Core, battery and LED (attached to D7). Onto the Core, I flashed the standard Web-Connected LED example from Particle and set up two IFTTT recipes with Google Assitant and Particle.
On IFTTT, choose the trigger "Say a simple phrase" from Google Assistant and then select the action "Call a function" for Particle. Select the function "led on #Your Core / Photon" and and enter "on" or "off" in the input field. And you're done. :)