Marcus Licinius Crassus was the richest Roman of his time. He invested in real estate, owned mines, and traded slaves, but he also acquired wealth in less conventional ways. He owned a private firefighting force, for Rome had no public one yet, and when he heard that a house was burning, he went there with his slaves. Once there, he would offer to buy the house for much less than it was worth. If the owner refused, he allowed it to burn. If the owner agreed, he would save the house and its belongings, and sell the house at a great profit.
Eager for glory, he led an army against the Parthians later in life. He was captured, and killed in the following way. Knowing of his greed for gold, the Parthians poured molten gold down his throat, thereby ending his life.