I first discovered this at an artsy cinema in SF. Brewers yeast, sure, but also nacho cheese powder, even ranch or dill pickle! (I haven't tried this cheese powder, but I have it on my list for popcorn and also for gluten-free instant mac & cheese).
To make sure you get everything coated (even if it’s just melted butter and salt), dump the popcorn into a paper bag, pour in the seasoning — trying to get it distributed without just hitting the paper bag — roll the top closed and shake like the dickens.
I personally also love making kettle corn which just involves adding equal parts sugar and oil (e.g. 1/4 cup sugar, 1/4 cup oil) to the pan before you add the kernels (1/2 cup in this example).
And one of my besties does a maple bacon popcorn for the first snow every year. ❄️