Do you hate those squirrels that bother your garden? Urine is an animal repellent. There's a lot of nitrogen in Urine so it can be useful in the garden. It is a fertilizer when diluted with water. The chemical industry used it in the manufacture of gunpowder. A nitrogen source, it was used to moisten straw which was kept moist and allowed to rot for several months to over a year. The resulting salts were washed from the heap with water, evaporated, and crude saltpetre crystals were collected.
Or what about fermenting urine to produce a solution of ammonia to wash cloth and clothing. That's the story of fulling. Fulling has specific urine requirements. Here's the story from Judy Zinni.
In the Scottish highlands and in Cape Breton (and Ireland), the local people would gather together to “full” the cloth - although the term used in Scotland is “waulking” and in Cape Breton “milling” or “fulling”. Harris tweed fabric was processed in this manner, traditionally. A long table, often with ridges carved into it, was used. People sat around the table and the woven fabric was stitched together at the ends to make a long loop/coil. The fabric was wetted down with a solution of water and aged urine (the urine of a young boy was preferred), which helped to shrink the fibres and cause them to become water resistant (in more modern times, a soapy solution was used instead). The people then sang waulking songs, a capella, which consist of short verses with a common chorus (in Gaelic). The songs had strong rhythms which were used to keep rhythm while pounding the cloth against the table top. They would pass the cloth to the person next to them during the procedure (remember the cloth is a big loop), this would ensure that the cloth would be evenly worked along its entire length. People from the community would save up their newly woven cloth and bring them to this community event (much like barn raising is a community event), and all the cloth would be worked at the gathering. In Scotland, the waulking was done mostly by women. This tradition was brought to Nova Scotia and was practised in Cape Breton, where it was done apparently primarily by men, although I’ve seen photos of groups of men and women together participating. After all the hard work, a “lunch” was served (usually in the late evening) and there would be music and dancing. In Ireland, the waulking was apparently done differently in a tub using the feet.
The waulking songs have survived through oral tradition and some tell of tragedies or events from the areas in which they were sung. A “leader” would sing the short verse, and the rest of the workers would sing the chorus together. In Cape Breton, there are sometimes demonstrations of this, known as milling frolics, and are put on for tourists.
