While reading this mouth-watering thread, I was reminded of a question I’ve wanted to ask:
I have a burr mill coffee grinder (manual) which I really like. I also like freshly ground spices. I was wondering if I ground spice, is there a simple and effective way to clean out the remnants so’s they wouldn’t flavor my coffee? I know I can buy a propeller grinder, which I already have, esp. for spices, but my coffee grinder grinds so nice and even, and doesn’t heat up as much as an electric.
Actually, some spice flavors might be kind of nice in coffee, but I’d like to control it.
So what? Salt? Oatmeal? Cornmeal? Forget it? 
Peace,
mangeorge
I’ve heard several foodies (that’s what they call themselves) recommend getting two coffee grinders, one for coffee and one for spices. It’s not so much a question of getting the spice flavor in the coffee as it is about getting the coffee flavor in the spices. Of course these same foodies generally recommend getting a mortar and pestle as well, because using THAT will get you different results than grinding or grating or mincing or chopping.
As for spice flavors in coffee, I like vanilla extract, cinnamon, and nutmeg. Not usually all together. I’ve also been known to put in a couple of spoonfuls of chocolate milk powder.
Ooh, Ooh, I can answer this!
Anyway, I clean my coffee grinder with a small pastry brush that I reserve for just that activity. It gets all the little grains out completely. I also have a second coffee grinder that I use for grinding spices. I try to pulse the grinder instead of constant use so that heat from friction is minimized.
And to answer the question from the propeller-grinder perspective, I used to just throw in a slice of fresh white bread and grind it up. It’s moist enough to pull most or all of the spice off of the grinder surfaces.
When I worked for Borders, we would use rice crispies (or the generic equivalant, whichever was on sale) to clean the grinder after a batch of the flavored coffee was run through (nothing worse than that lingering flavor of ‘pumpkin spice’, if you’re the type that thinks flavored coffee is a sin against God).
It worked well. Any lingering bits of crispie would not affect the taste of the next batch. I don’t know about actual ground spices, but if you only do it once in a while, you could run the cereal through 2 or 3 times, and really clean it out. Get one of the big bags of Malt-o-Meal brand crisped rice cereal, as it’s not a big deal if it is fresh or stale.