Exactly this for me as well - think people really underestimate how fast it allows you to iterate through prototyping. It's not outsourcing your thinking, it's more that it can generate a lot of the basics for you so you can infer the missing parts and tweak to suit your needs.
I mainly use it for taking text input and doing stuff that's easy to describe but hard to script for. Feed it some articles and ask for a very specific and obscure bibliography format? Great! Change up the style or the wording? Fine. Don't it ask for data or facts.
* Rapid prototyping and trying new technologies.
* Editing text for typos, flipped words, and missing words