Medical marijuana brings "green rush" to Colo.

Colorado's thriving medical marijuana business isn't just named for the color of today's green, potent pot. It's the color of the money being made in the medical marijuana industry. Steve Kroft goes to the Rocky Mountain state to report on a business that's legal there and 16 other states, but in the eyes of the federal government is still as illegal as dealers selling heroin or LSD. "Rocky Mountain High" will be broadcast on 60 Minutes Sunday, Oct. 21 at 7:30 p.m. ET and 7:00 p.m. PT.

Kroft goes to Denver to visit a few of the city's 204 medical marijuana dispensaries -- shops so numerous, they outnumber Starbucks and McDonald's combined by nearly threefold. The state of Colorado, with five million people, boasts a total of 537 medical pot dispensaries and more than 100,000 authorized medical marijuana patients.

Highly regulated shops sell medicine patients can smoke with names like Jack Frost and Biodiesel; edible versions of cannabis are also available, from the newfangled, like ice-cream, sparkling sodas and chocolate, to old standbys like cookies and brownies. A webcast to go live on Sunday evening on 60MinutesOvertime.com will feature a whole segment on the various kinds of marijuana-infused edible products Kroft found.

The rush, like those for silver or gold so long ago, is attracting investors, or as some call them, "ganjapreneurs." Kristi Kelly came to Colorado to make money on marijuana. "There's not a lot of opportunities in any one lifetime where you can be part of something from such an early stage," she tells Kroft.

The federal government has done little in the state to interfere in the booming trade. And even if it chose to, the sheer number of dispensaries would present a daunting challenge. The Justice Department, however, has warned that financial institutions could be prosecuted for handling money from such businesses. This is a situation ganjapreneurs cannot tolerate much longer as their businesses grow larger.

This past week, a federal appeals court in Washington held a hearing on whether to change marijuana's status under the Controlled Substances Act. Medical marijuana advocates are suing to remove cannabis from the Schedule One list and reclassify it as a drug that could be prescribed by physicians.

Meanwhile, Colorado could become the first state to legalize pot. A referendum is on next month's ballot that if passed, would legalize recreational use of marijuana with regulations.