In fact, according to a new study, it's now moving well over $100 million of illegal substances a year, and it's recovering from every new scam-induced setback and government crackdown faster than the last one.

Those are a few of the lessons from a deep-dive study into Dark Web black market sales statistics that a pair of Carnegie Mellon researchers plan to present at the Usenix Security conference Wednesday. From 2013 to early 2015, they used automated software to "scrape" the visible contents of 35 Dark Web markets, counting the number of feedback ratings that the major drug sites require buyers to leave after each sale and then multiplying them by the purchased item's listed price to gauge total sales volumes. The result is the most comprehensive—if still not fully complete—picture of how contraband narcotics sales have waned and waxed during the short history of the Dark Web's online economy.