Crewing: Think “pit crew” a la NASCAR. Taking care of a horse/rider team before, during, and after an endurance ride. Sometimes entails driving to out-of-the-way locations to the vet checks, spending 24+ hours awake, getting covered in slobber, mash, and other delights. Crewing is fun.
My own personal specialty is crewing at Tevis, which is a special kind of fun.
I can also occasionally be talked into/lose my mind and volunteer to crew or pace for friends at ultramarathon trail races.
20 Mule Team 2013
Black Canyon Ultras 100k 2017 (crew/pace)