News, Fox, CNBC, Mashable and other outlets.Musk, famous for PayPal, Tesla Motors and SpaceX, invited Oster to California this summer to talk about the technology.Oster said Musk told him he would not take the lead on any project but that he would invest in a 3-mile prototype that ET3 plans to break ground on soon.Elon and his teams must focus on Tesla and SpaceX, said SpaceX spokeswoman Christi