If you saw a nickel on the ground, would you pick it up? Would your answer change if it was a $1 bill? How about a bag of $100 bills?

Thus far in 2017, short volatility traders have been picking up the equivalent of industrial-sized garbage bags filled with $100 bills. In shorting equity volatility – via ETFs, futures, or options – they have been earning what seems like a risk-free reward. Volatility has never been this consistently low for so long, and shorting it has therefore never been easier.

But the word around town is finally getting out. It is hard keep traders quiet for long when they are picking up bags filled with $100 bills.  Non-commercial futures traders have built up their largest net short volatility position in history. Every one, it seems, is lining up to receive their free bags of money.

What could go wrong here? Nothing at all, I’m sure, unless by some freak occurrence there happens to be a bulldozer or steamroller passing by.

For a long time the geniuses at Long Term Capital Management (LTCM) picked up nickels in what seemed to be a risk-free arbitrage. With annualized returns of almost 40%, those nickels added up to a nifty sum. And then, just like that, it was gone. A steamroller passed by in May 1998, and then another in June, and then a few more in July and August.

By September 25, 1998, LTCM’s equity moved down to $400 million. With liabilities of over $100 billion, they were leveraged 250 to 1. The partners of LTCM once had $1.9 billion of their own money invested in the fund, all of which was wiped out. A bailout by the Federal Reserve Bank of New York was organized to prevent a wider financial collapse.

It’s been almost 20 years since LTCM and nearly 10 years since the 2008 financial crisis. Memories fade and new traders without that emotional baggage have entered the markets.

How many of these traders today have leveraged short volatility positions on, operating under the assumption that volatility will stay low forever? I don’t know, but we’ll find out soon enough. The names change but the moral of the story never does. If you pick up nickels long enough you will one day look up to find a steamroller inches away.

Think you can move out of harm’s way in time? Indeed, as does everyone else.