Bleeding-edge entrepreneurAfter selling PayPal to eBay for $1.5 billion, Musk has parlayed his estimated $334 million fortune into three ventures: As chairman at Tesla Motors, he hopes to give the electric car market a big jolt. Musk's SpaceX has successfully launched its Falcon rocket, a bargain at $7 million per flight. Then there's Solar City, another Musk company, which encourages neighborhoods to share the cost of installing solar panels.
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