And yet bitcoin—backed by a community a people who are often vigorous in defending their rights to privacy and attracted to cryptocurrency as a way to disengage with established government systems—doesn't really want to be tracked. The promise of anonymity, tenuous though it may be, is what makes bitcoin an ideal currency for someone who wants to buy something they shouldn't.

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Like virtually every other realm of commerce—legitimate or underground—the Internet has upended the fake ID business as we once knew it.

A dozen years ago, you could still buy a fake ID by walking into a nondescript luggage store in midtown Manhattan and saying the word "Arkansas." Store employees would pull camera equipment out of a suitcase right there on display, photograph you in front of a blue fabric backdrop, type up a fake birthday and address on a typewriter, then laminate the thing on the spot. You'd be out $50 but into any number of dive bars in the area.

Today, like everything else, these sorts of transactions have moved online. "The subreddit for fake IDs is how I found the places I wanted to order from," said Jake Ryan, a marketer who ordered two fake IDs at about $150 apiece as part of a project for the website detox.net.

One of the IDs never showed up. (The company that didn't deliver is called, ominously enough, DarkMark IDs.) The other ID arrived embedded in one of the pages of an air-conditioning manual.

"I don' t know how they sealed it," Ryan said. "If you just gave someone this manual, they may have never seen it." Though Ryan says the ID appears to have been sent from Taiwan, the website where he placed the order—new-ids.com—is registered with a San Diego address.

And the ID looked only semi-passable compared with a real Florida license, Ryan says, or, it would have if it didn't feature Family Guy protagonist Peter Griffin, who is a cartoon. Ryan deliberately ordered the ID with Griffin's face on it so that it was clearly novelty item. The Secret Service has orchestrated stings selling fake IDs online as a way to catch the people who try to buy them.

Here's a real Florida license compared with the the fake that Ryan ordered:

Plus, check out some of the other states advertised on the same site—if you know what these state's licenses actually look like, you can probably tell the fakes look familiar, but aren't exactly matches.

"The immediate first impression was that even if it wasn't a cartoon character, the colors were kind of off," Ryan said. "You could tell it wasn't 100 percent passable."

Bartenders and bouncers generally agreed with him. (This wasn't a perfect test, though, as the people he asked knew what they were about to see was fake.) Curiously, however, Ryan says the fake easily passed a scan test. When he ran the ID under a scanner app on his iPhone—technology similar to the kind used to check driver's licenses at some bars and clubs—the details he had entered when he ordered online appeared. "It had all the information: name, date of birth, address, all that stuff," he said.