A smoothie made by the Jamba Juice fast food restaurant chain, typically made with an ice cream substitute, sugared fruit juice or sugared soy milk, and fruit. Tasty, but usually not healthy.
It is basically a mixture of bodily fluids, which is a reference to the actual Jamba Juice store. To be specific it is basically a mixture of the water that comes out of a girl after she uses a douche and her urine. A urine and douche-water cocktail, to simplify.
Man, Megan Fox is so hot, I would drink her jamba juice!