But reasonably sophisticated investors can create the same product themselves by purchasing a risk-free zero-coupon Treasury bond and call options on a stock index, such as XSP options traded on the Chicago Board Options Exchange.

FORBES: Guaranteed to Go Up

Last year, Harry Kat, a professor at City University's Cass Business School in London, and three others used American stock and bond data from 1970 to 2003 in thousands of simulations measuring risk and return on ten-year Treasury bonds, alone and in more diversified portfolios.

ECONOMIST: Buttonwood