Negative interest rates are coming and they are downright terrifying

In the U.S. we aren't particularly aware of negative rates because they haven't made their way to our shores ... perhaps yet.

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in Europe, it was postulated that negative rates would never fly in the consumer sphere in terms of banks paying back depositors less than they put in their savings accounts, but that's now changing. Banks in Denmark and Switzerland are now charging customers to hold deposits. And on the flip side, and also in Denmark, mortgages with negative rates are available. That's right, you get a mortgage from the bank, and the bank essentially pays you each month. A three-year adjustable rate mortgage priced at negative .28% there recently.

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What would happen if rates go negative in the U.S.? Who knows. Allianz Chief Economic Adviser Mohamed El-Erian, for one, says he would sound the alarm if treasury yields dip into negative territory. "If we do I'm going to be really worried because negative yields in the U.S., the world's biggest financial market, will break things," he told Yahoo Finance.

... [and] there are some pretty serious negatives, certainly from the standpoint of uncertainty. A recent note by JPMorgan lays out nine unintended consequences; including lower bank profitability, lower credit creation, paradoxically higher rates in some instances (banks need to make up for lower income), reduced liquidity and functionality of credit markets, increased deficits in pension funds, and even exacerbation of wealth and income inequality.