Here, bs is gold. Literally. It gives you warmth (if dry), it acts as a great caulking substance (if wet), it is smokeless, odorless and it costs you nothing.
Someone has to collect it. Someone has to walk behind the camels gathering their dung all day long. Someone grabs, bare-handedly, each pile of fresh bs that falls to the ground, puts it into tightly woven burlap sacks, and carries it home, fully aware that his family depends on this bs for survival.
At home, someone makes patty cakes with it, arranges these into piles outside the yurt, and lets the piles of bs dry in the sun. When they are ready for use, they are brought into the yurt, placed into the fire stove, and lit with a match. Within seconds, the near-freezing yurt is transformed into a near-sauna. No wires or outlets needed. No prohibitive electricity bills at the end of a brutal winter. No negative impact on the environment. Nothing. It is, as far as I can see, the most effective and the purest source of heat. Then again, someone has to manipulate it, which we did without a hint of repulsion. But as luck would have it, as soon as our gracious hosts retired, so did the fire in our stove. And that's when we discovered the extent of our inadequacy. Apparently, throwing a lit match into the urn of bs is not enough to get it going. Suffice to say that we ran out of matches and ended up using a camping stove and starter blocks.
When I told a friend that I was going to Mongolia, all she wanted to know was why. Why? Why? of all places. This picture is the answer. He is a Mongolian shepherd through and through, herds his family camels and sheep like his ancestors did, and he does all of this with a few modern twists. There he is in the middle of nowhere in Mongolia, inside his yurt (the motorcycle he uses for herding is parked outside by the door), talking to a fellow shepherd over his mobile phone. In front of him hang the tails of the animals he has sold. For good karma. So that the spirit of the animal can come back home whenever it feels the tug; so that the exchange of a sentient being for money doesn't become a curse; so that animal and shepherd reincarnate in higher forms; so that they can recognize, acknowledge and cherish each other again and again.