"Alexa set a timer for 15 minutes." (She's a cooking timer)
"Alexa what time is it" (She's a clock)
"Alexa switch the tv off" (She can't switch it on)
"Alexa, meow meow/Pika/fart" (Novelty nonsense)
"Alexa, turn the heating up in the living room" (Nest integration)
Yeah that's about it. The only really useful thing she does for us is music control on our sonos system - "Alexa, play the album X by Y in the kitchen". That's quite neat.