The Gold Bug

In Ian Fleming's Goldfinger, the eponymous villain, heavily invested in gold, sought to increase the value of his horde by destroying the United States' gold reserves at Fort Knox.

It would have been far more lucrative for him to boost demand for gold, rather than reduce the supply, by destabilizing the world's economy.  Rather than employing a specialist assassin like Oddjob (who probably didn't work cheap and likely incurred very large equipment and cleanup expenses), he could have employed some lobbyists and creative investment brokers to invent complicated debt-based investment vehicles, then pull down the house of cards and watch the value of gold skyrocket as the world financial markets imploded and government bonds were downgraded.

Maybe the upcoming Bond 23 should be a remake of Goldfinger.  Of course, people may have trouble believing that a criminal conspirator could con everyone into driving up the price of gold.  Oh, wait...