George Soros is known as the wealthiest speculator of all time. His trading all took place in the Netherlands Antilles, where his earnings compounded tax free.

http://www.turtletrader.com/oig.html

In 1970, this Hungarian-born contrarian investor-philosopher created the Quantum Fund with Jim Rogers… It went on to return about 3,999%, compounded, over the next 30 years… Soros is famous for going short the British pound and earning $1 billion in a single day, Black Wednesday, 1992.   He was dubbed the "Man who broke the bank of England" for his move, which forced major reforms to the British banking system. Today he fights the "evils" of the U.S. brand of capitalism even while profiting handsomely from it (he's worth an estimated $7.1 billion).

http://www.investment-u.com/ppc/splash_soros.cfm?kw=XVVIU317