RICK CUSICK, the associate publisher of the marijuana magazine High Times, remembers the first time he saw a vaporizer. It was in 2000, at a tobacco trade show in Las Vegas. “I was having a party in my room at the Sahara,” Mr. Cusick said, “when two men walked in carrying a 50-pound drill press attached to a plywood board.” The drill press had been set up with copper tubing to heat cannabis just enough so that its active ingredient, tetrahydrocannabinol, was released not as smoke but as a less scorching vapor.

“Stoners are a very creative lot,” Mr. Cusick added.

They are also resourceful. As medical marijuana has gained public support (it is now legal in 16 states and Washington) the increasingly popular vaporizer may soon emerge as a cultural alternative to the bong or hand-blown glass pipe.

“Our vaporizer sales have jumped over 30 percent each year for the last four years,” said Elijah Kliger, owner of the SDR Shop, an online head shop based in Brooklyn. His site currently stocks seven models, from $37.49 to $62.49, which the site states are “sold with the express intent to be used with legal herbs and oils for aromatherapy purposes.” The sale of vaporizers explicitly for marijuana remains illegal under federal law, even in states where medicinal marijuana is legal. For this reason, vaporizers are marketed as an aromatherapy device, to be used with household herbs like lavender and eucalyptus.

That would explain how they are sold in the open. Salman Shahid, a clerk at Shisha International, a West Village tobacco shop, said he stocks 22 types of vaporizers, up from 5 in 2007.