Answer:
The possibilities of lemons are endless.
Have enemies? Best weapon is a lemon: Cut open and squirt generously (or malevolently) into enemy's eyes.
Have a pie to bake but it's summer and there's like, no seasonal pie for summer? Lemon pie is a winner among the summer months because of it's sunny flavor.
Lemons clean stains out of rugs and other things.
The skin of lemons (and hell even the fruit) make good compost when you want to grow something you can actually eat.
For some reason during hot summer days my friends liked to suck on lemons. I preferred oranges but hell give it a try.
You can use lemon zest (don't know what that is? Well I'm sure you know how to use google) to liven up any boring recipe
Wanna bet but you have no idea what terrible pain you want to inflict on each other? Use your imagination, the lemon is painful and normally won't cause too much harm to anyone.
Also the standard lemonade and using it to sterilize water.