Reusing old spice containers

I had a little tin of pimenton I really liked and by the time I got to the end of it all that was left was a fine coating of red dust and a real strong pimenton aroma. So I poured some kosher salt into it, forgot about it for a few weeks, and just remembered and sprinkled some over sourdough, avocado, sardines, olive oil, and white wine vinegar. It's neat! Just enough paprika sweetness to add something without overwhelming.

I've heard of perfuming salt with spent vanilla pods, but does anyone else go beyond that?