I’ve only used it once, so far. My players were in a place that was supposed to have prayers to an apocalyptic world-devouring entity written in secret text that could be discovered by the players.
I knew my players were likely to find it, so I asked ChatGPT to write out the text of these dark apocalyptic psalms. It did a great job, and when my players discovered the text it was appropriately verbose and creepy, instead of me just saying “you find prayers to the World Devourer”.