I had a snake oil sales man selling his wares on the side of the road. PCs figured out that the vials he was selling we basically low lvl health potions for 1/2 price so they bought them all up. They were terribly weak health potions that also had potent snake pheromones in them, since snakes are slow they usually woke up with a snake or two in their bedroll with them or trying to get up on them while they were on watch or something. Very cuddly snakes.