I've always known that you can roll a lemon back and forth across a hard surface in order to release the juices and get as much out of it as possible.
Buy my grandma taught me another trick when I was cooking with her this week: microwave the lemon for 15 seconds! She said this will produce twice the juice, which is particularly key for those hard-to-squeeze lemons. And it totally works! Just be sure not to microwave it for too long—or it will explode!
What tricks do you have for getting the most juice out of lemons?