One of the oldest life forms on Earth, spirulina is a blue-green microalgae that helped produce the oxygen in our atmosphere billions of years ago so that other life forms could appear (http://www.chinese-herbs.org/spirulina/). The original 'superfood,' spirulina is so nutrient dense that you could survive on it and water alone. source
Spirulina also claims to be good for your skin and detoxing your liver. It sounds really promising so I'm going to try this super algae. Let's hope it really works!