Bitcoin investors are having a wild ride. The best-known cryptocurrency quadrupled in price in late 2020 -– a surge reminiscent of its heyday three years earlier, when it rocketed to nearly $20,000, then crashed and lost more than two-thirds of its value. Once seen as the province of nerds, libertarians and drug dealers, there’s still little sign it will evolve into a useful form of money for most transactions. Yet the latest bout of roller-coaster volatility comes as more big investors are spec