This is one of my all-time favorite smoothie recipes. I never used to think that I liked grapefruit juice, but that was because I had only had the acidic kind you find in a carton (aka pasteurized). When it comes to flavor, fresh juice is in a league all its own (and is better for you anyway).
2 grapefruits, juiced
1 ½ small bananas, frozen(I used to use 3 pieces, about 1 large banana, but bananas seem to be getting smaller and smaller, so this may need to be something you play around with)
1 cup frozen strawberries
Blend and serve. Better with a straw! You could also call this a flamingo smoothie for reasons of color.