(FORTUNE Small Business) – What can early Christians teach modern entrepreneurs about guerrilla marketing? Students at Union College in Schenectady, N.Y., are facing questions like that this month on their final exam for a new course titled Entrepreneurship in the Ancient World. "Ancient economics, law, history, and literature can yield profitable lessons about everything, including entrepreneurship," says classics professor Hans-Friedrich Mueller. As for early Christians, they did their marketing the way today's hip sneaker makers do, by sending street teams to poor neighborhoods and then waiting for their "product" to move up the social strata. There are cautionary tales too. The Roman general Crassus built a real estate empire in part by running a private firefighting company that offered to purchase burning buildings from their owners (rumors had it that his firefighters also served as firestarters). Mueller, 45, warns that Crassus's unbridled ambition led him into a military campaign in which he lost not only the faith of his army but also, alas, his head. --IAN MOUNT