According to Wikipedia, Urine (colloquially known as "Pee"), is liquid waste product of the body secreted by the kidneys by a process of filtration from blood and excreted through the urethra. This waste is eventually expelled from the body in a process known as urination. However, Urine is not a dirty and toxic substance rejected by the body, it is a by-product of blood filtration, not waste filtration.

We think of human pee as gross and something that ought to be vigorously "cleaned up" or sanitized. However, human urine is actually sterile (unlike feces, urine is bacteria-free). Far from being a dirty body-waste, fresh, normal urine is actually sterile and a mixture of some of the most vital and medically important substances known to man. It contains minute amounts of proteins made by the body, including medically important ones such as growth hormone and insulin. It is estimated there is a $500-million USD-a-year market for these kinds of ingredients. Whilst the idea of recycling urine is not new, it needs thousands and thousands of liters to commercially produce products

Urine therapy is also an age-old practice of Humanity, especially in ancient India. It is considered effective in treating a wide array of diseases such as multiple sclerosis, colitis, lupus, rheumatoid arthritis, cancer, hepatitis, pancreatic insufficiency, psoriasis, eczema, diabetes and herpes.

Modern Uses

Recycling urine may be the answer to a looming global shortage of phosphorus and other essential nutrients which are key component in agricultural fertilizers, an Australian researcher says. Examples of commercial medical applications in use today are: Ureaphil: a diuretic made from urea; Urofollitropin: a urine-extract fertility drug; Ureacin: urea cream for skin problems; Amino-Cerv: urea cream used for cervical treatments; Premarin: a urine-extract oestrogen supplement; Panafil: urea/papain ointment for skin ulcers, burns and infected wounds. Another urine-related product ingredient is carbamide, which is the chemical name for synthesized urea. Carbamide is used in products like ear drops and skin moisturizers.

Innovative Ideas

As environmentalists worry about water shortages, more states are turning to an old NASA trick: recycling urine. Nutrients are not waste, and therefore should not be considered or treated as such, and although urine recycling is a foreign concept in a modern society, many innovative entrepreneurs have brilliant ideas on how we can take advantage of this resource, from urine separating toilets to generating power from our own wastes:

• The Secret Formula of Pee-Powered Batteries: Japanese company Aqua Power manufactures batteries in various sizes that are using liquids as a catalyst causing a reaction between aluminum and magnesium resulting in a reload of the battery. Various liquids, such as water, coke, beer and even urine can be used. The Non Pollution Power batteries are brand named NoPoPo, as the batteries are eco-friendly, not using lead, cadmium or any other fossil combustible.
• Flush your Toilet for Electricity: Leviathan Energy, based in Los Angeles and Israel, has created a turbine that would create power from the downward flow in municipal water and sewer systems. In other words, whenever you flush, you'd be helping generate electricity. Rushing water is good at driving turbines -- that's the basis of all hydroelectric power. Usually, those turbines are located in rivers, but what about other sources of water, like wastewater runoff? There is nothing really new here; it is the location and scale of this system (i.e. in your toilet!) that makes it such an innovative product.
• Make Millions, Recycle your Pee: DrinkPee is a project about the role our bodies play in larger ecosystems. The project includes an installation and a DIY kit for turning your pee into fertilizer, using a scale down version of the aforementioned process. This kit gives users the opportunity to replicate the new technique at home and fertilize their plants with their own pee. The project was created by Britta Riley and Rebecca Bray, two artists and collaborators who also own a company called Submersible Design.
• Turn your Pee into Electricity: Nanologix has a patented renewable hydrogen production method that instead of using the traditional energy wasting methods requiring natural gas or electrical power, creates the gas out of waste water and other biomass using bacteria in a "Hydrogen Bioreactor".