Using up all your kitchen scraps helps you get the most for your money -- especially when it comes to expensive ingredients like olives. Try dropping the leftover pits into extra virgin olive oil to add a fruity flavour.
Image from cjtrigg
This tip comes from Bon Appetit and is especially helpful if you buy olives by weight. You're paying for the pits anyway, so you might as well get some use out of them. When you infuse oil with other ingredients (by allowing the ingredients to sit in the oil and impart their flavour), you'll end up with an even more intense flavour (think green apple or apricot) for relatively little work.
However, you may be reducing the life of the oil by adding the olive pit, so try to use the oil up quickly. You can always transfer the oil you want to infuse to a smaller bottle so you have less to consyme. Just as you would use extra virgin olive oil to finish dishes -- drizzling it over soup, grilled veggies, or in a salad dressing -- you can use your newly-flavoured oil in the same way.