What part of your body would you be willing to lop off just to come up with just a single million-dollar idea? Elon Musk is so business-savvy that he's created or co-founded not one, not two, not three, but four companies that are worth more than $1 billion each: PayPal, Tesla, SpaceX and SolarCity. And notably, he still has all his limbs and fingers.
SpaceX is valued at more than $20 billion, and Tesla is worth nearly $60 billion in 2018 [sources: Foust, Martin]. SolarCity was bought by Tesla for $2.6 billion in stock. It was originally started by Musk's cousins and he invested $10 million in it in 2006. SolarCity designs and sells solar panels for residential and commercial purposes. Both Tesla and Solar City share the goal of making sustainable energy more practical and efficient [source: Carr].
Musk knows that charitable causes come with the territory of extreme wealth. He gave $15 million to the Global Learning program, which is meant to help unprivileged children around the world boost basic skills in reading and math [source: Zaidi].
In the wake of the terrible 2017 Hurricane Maria, he sent huge battery systems that can be powered with solar panels to bring electricity back to Puerto Rico. He also donated hundreds of thousands of dollars of his own cash to the cause.
And he's joined the ranks of filthy-rich folks who commit to philanthropy. He signed the Giving Pledge, an idea conjured by billionaire investor Warren Buffett, meant to spur more charitable donations. Signing the Giving Pledge means agreeing to leave at least 50 percent of your wealth to charity either during your lifetime or in your will [source: Zaidi].