I have recently been very stingy with my paint. I squeeze out and mix a palette that I will need over several days, but I have been scraping it off and throwing away good paint at the end of the day because the piles tend to dry overnight.
I bugs me to waste paint.
No more.
Now I stick my palette in the freezer, and my piles come out the next day ready to use within minutes. I notice a tiny tiny amount of condensation on the piles when they come to room temp, but I mix the pile up a bit and the paint seems just fine.
I had heard of this practice, but had never tried it. Glad I did as it saves a little paint.