Just made Brazilian "Lemonade" (actually limes) this weekend, pretty tasty.
For the adventurous:
4 limes, split 3x (so 1/8s), peel and all
1 can (7 oz.) condensed milk
1/3 cup sugar
4 cups of water
4 cups of ice
Blend everything but the ice on a low-ish setting (don't want to blend that peel...