The sinking of the Titanic is possibly the most famous accident in the world. But it barely makes our list of top 10 most expensive. On April 15, 1912, the Titanic sank on its maiden voyage and was considered to be the most luxurious ocean liner ever built. Over 1,500 people lost their lives when the ship ran into an iceberg and sunk in frigid waters. The ship cost $7 million to build ($150 million in today's dollars).