Is Human Pee the Future of Fertilizer?

Among the things I found mortifying about my parents when I was a teenager was their habit of leaving buckets of pee in the bathroom. Instead of flushing all that phosphorous- and nitrogen-rich urine down the toilet, they saved it for our backyard vegetable garden. Pee as fertilizer has since--contrary to everything my teenage self wanted to believe--become a hip idea among some eco-minded backyard farmers.