It's no longer the world's only Options Exchange, but the Chicago Board Options Exchange remains the largest. Founded in 1973 by the Board of Trade, the exchange lists options on some 1,500 stocks. Designed by the architecture firm Skidmore Owings and Merrill (of Sears Tower fame), CBOE is a bit of a tourist attraction for the Wall-Street-type crown. The visitors' gallery is currently closed, but you can contact CBOE regarding tours.