Citrus Zest

You can also dry it and then pulverize in a spice grinder (with salt or sugar if desired, or just on its own) and keep it as a powder.

I have gotten out of the habit of doing this, but I always used to zest any citrus I was juicing for a recipe, then keep it in an airtight bag or jar. So handy when you get in the middle of a cookie or bread recipe and realize, "Oh no! I should have bought an orange at the store..."

I always zest and freeze Meyer Lemons when I get my hands on them. I place my zest in a ziplock freezer bag, press out the air and pop it in the freezer. I try to use up a batch with in three months -- usually not hard to do.