Thomas Peterffy

Born in Budapest in the middle of WWII. Peterffy spoke no English when he emigrated from Hungary to the U.S. in 1965. Started out as a draftsman, then taught himself computer programming. Bought his own seat on the American Stock Exchange in 1977 and started Interactive Brokers in 1993. Unclear how much his personal stake is, but even the most conservative estimate ranks him on the Forbes World's Billionaires list. Avid equestrian keeps horses at his Greenwich home.