Digital coins may well change how people buy and sell goods one day, but for the moment they're mostly an investment, and a remarkably tough one to use and secure.
That's why so many fund companies want to start exchange-traded funds that will track the price of digital coins and trade like any other ETF in a brokerage account. The Securities and Exchange Commission has so far squashed these hopes, citing the volatility of cryptocurrencies, among other reasons.
