Dice. :mrgreen:
My small layout uses the Inglenook Sidings as a yard, and I roll a d8 5 times for the outgoing manifest, rerolling duplicates. Then a d6 for where each car goes on my industries (again, rerolling duplicates).
This gives me (8*7*6*5*4) * (6*5*4*3*2) possibilities, this...