Cryptocurrencies have been all the rage for the past year or so, creating substantial wealth for investors who bought these virtual coins anytime before the beginning of 2017. Some of the most popular, like Litecoin, Bitcoin, Ethereum, Stellar, Unity and Ripple, have generated enormous returns for anyone who bought, mined, or otherwise acquired these digital currencies soon after they came into existence. We are talking about gains of between 4,000% and 17,000,000% -- potentially life-changing wealth.