The gadget craze has created several fortunes, making billionaires of William Cook of Cook Group, who used a blowtorch to make an early catheter, and John Abele, cofounder of Boston Scientific.

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Consider three big earners on our list: Larry the Cable Guy, Jeff Foxworthy and Dane Cook, all of whom are making six or seven figures playing a circuit of stadium venues at lofty ticket prices.

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Mr. Cook wouldn't detail whether Apple would consider making a cheaper version of the iPhone, especially for prepaid wireless customers in emerging markets.

WSJ: Apple Defends Position on Cash

Mr. Cook wouldn't detail whether Apple would consider making a cheaper version of the iPhone, especially for reaching prepaid wireless customers in emerging markets.

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