It used to drive me crazy reading recipes that called for lemon zest only. I could never manage to have enough fresh fruit on hand. Either I had used the zest leaving me with a naked lime that dried out or I'd only needed the juice and had to toss out all that prime, waiting-to-be-zested peel.
Fast Fact: Freeze juiced halves of citrus instead of throwing them away. You can zest them with a microplane (while frozen) to add zip and flavor to cakes, bread, muffins, whatever you're cooking up.
What of those zested un-juiced fruits?
Bonus Fast Fact: I found that if I wrap them in plastic or fold them in a sandwich bag they don't dry up as fast and I can keep them in the refrigerator for up to a week! The plastic steps in as a substitute peel keeping it from drying out so quickly.
No more waste.