So far, the best combination of neat and useful for me has been integration with Logitech Harmony and having Alexa start turning stuff on while I approach the couch. It feels so futuristic to be able to shout in to the air that I would like to watch some TV or play a game and have all that stuff just come up for me. If I spent more time with it, I could probably even get it turning to specific channels or launching Rocket League automatically. I tried doing the normal shopping list routine with it, or asking it to set timers, but none of that has really stuck in the same way that "Alexa, turn on AppleTV has." I do like her sense of humor though, and "tell me a joke" is a mainstay.

Twitch streamers do this sometimes, and it's usually purposely choosing an annoying song.

I like to use it for situationally-appropriate accompaniment. Just won a game of Pandemic? "Alexa, play 'We Are the Champions'." Just lost a game of Pandemic? "Alexa, play 'It's the End of the World as We Know It'." :)