In 2003 the total size of the world economy was $49,000,000,000,000. The total size of the derivatives being traded was $85,000,000,000,000. In other words, derivatives today are worth far, far more than the total economic activity of the planet. More than $1,000,000,000,000 of derivatives are bought and sold every day. Cityphilia
(A completely unfair comparison, but catchiness counts)