I just powdered a quick salt and spice blend in my blender, and it dawned on me that there might be a few folks who enjoy experimenting in the kitchen who are unaware of this very simple tip. The threads on standard canning jars match the threads on most blenders. If that doesn't make you go, "damn that is so cool..." let me explain. First, not only canning jars have those threads but standard mayonnaise and peanut butter jars do, too. And they have lids.
What I did with the salt and spices was measure it into a mason jar, then put the screw-on cutter from my blender on the jar like a lid. The little jar was so small and light, I could easily stick it on the blender base, then pick the entire thing up and shake it around to make sure everything made it into the whirring blades. You can add dressings and marinades to a cleaned mayonnaise jar, puree it, then put a lid on and store it in the fridge. If you want to re-homogenize before use, it's really easy.
And if anyone has ever been disappointed in the grind from a store coffee grinder, sifting the larger shards into a mason jar and blending makes it possible to use the stuff. Glass is quieter for this than plastic. Just in case it's early in the morning.
Little tip. Lots of uses. Jerk marinade, with spices, lime, peppers and garlic comes to mind.