I finally made it! Ahhhhhh! My gray brain hat got picked up in a really pretty treasury.
https://www.etsy.com/treasury/MTIxODk4NTR8MjcyMTY1NTU0OQ/massage-for-your-brain?index=15
I got to see it on my phone, but I didn't get a screen shot. Still, super cool! :)
This demonstrates why it's important to have separate listings for separate colors instead of using listing variations - my pink brain hat probably wouldn't have fit very well with this treasury, but my gray one was very nice. :)