Goodness! Where to start? Under Hollow Hills is such an interesting variation on the PbtA model. I love its focus on a relational model for actions and constantly changing characters. It's deeply inspiring in what I want to make!
Edit: I got a chance to play this recently, and it was delightful. I played as a human who loves fairy, even when she doesn't belong. Just as great in play as to read. I'm looking forward to the next time. Hopefully soon!