I discovered today that some people use tea to wash hardwood floors for a nice shine, and now I have plans for that tannic terribleness that's been in the cabinet a long time.
Today I also successfully mixed some olive oil with tarragon vinegar we've had around for ages, as a wood table treatment (smells better than white vinegar). Earlier today I put unused fresh rosemary in a jar of nasty citron vodka I wouldn't drink, to see if I can get a nicely-scented cleaning spray out of the deal within a few weeks (am likely to add lavender between now and then).
Any other ways you use up food items in a nonfoody way? (Besides charity and compost.)