From the Sand Pit: It's freezing here. I'm sitting on hard, cold dirt between rocks and shrubs at the base of the Hindu Kush Mountains, along the Dar 'yoi Pomir River, watching a hole that leads to a tunnel that leads to a cave. Stake out my friend, and no pizza delivery for thousands of miles. I also glance at the area around my a-- every ten to fifteen seconds to avoid another scorpion sting. I've actually given up battling the chiggers and sand fleas, but those scorpions give a jolt like a cattle prod; hurts like a ba---rd. The...