Been messing about a bit lately!
My big experiment has been trying to reproduce the Ukrainian method of milk-firing pottery. I started with a fired pot, mainly red in color, and I gave it a few baths with whole milk. Then I stuck it in my oven, turned it up all the way (550°F in my case,) and let it bake for about an hour.
The baking period caused the milk to turn dark brown and permanently fuse to the pot!