On Saturday morning at the Cow Palace, a 15,000 seat indoor arena located just south of San Francisco, the nacho concession was surprisingly deserted. But it was early yet, and given the long line of people who were waiting to gain access to the Prop 215 Tent at the International Cannabis and Hemp Expo, business would eventually pick up. After four years of wrangling with local officials, the Expo's promoters had managed to obtain a permit that would allow on-site pot-smoking at the event, and the Prop 215 Tent, where attendees equipped with medical marijuana cards could light up, vaporize, consume medibles, or otherwise treat themselves, was the early favorite for most popular attraction.

Even for those without a card, the Expo was fairly mind-blowing. There are hundreds of medical marijuana dispensaries in California now, and between them and all the illicit dealing that goes on, annual marijuana sales in the state are estimated at approximately $14 billion. Given the state's terminally ill budget, proposals to legalize cannabis for all adults is gaining momentum: A marijuana tax won't cure a $20 billion shortfall, but at least it could offer some minor pain relief.

In November, residents will vote on Tax Cannabis 2010, an initiative that would make it legal for anyone 21 or older to possess up to one ounce of marijuana while giving local governments the power to tax and regulate commercial production. Meanwhile, California Assemblyman Tom Ammiano is pushing a similar proposal in the state legislature that would legalize marijuana for adult usage and subject it to a $50 per ounce excise tax. While either proposal could end up generating as much as $1.4 billion in revenue for the state, what the International Cannabis and Hemp Expo made clear is how much ancillary economic activity the trade is already generating.

With approximately 150 exhibitors showcasing their wares and pitching their services, the Expo isn't quite ready to fill up a Vegas-sized hall, but for a semi-permitted industry where severe legal repercussions are still a very tangible cost of doing business, the degree to which the marijuana trade has mainstreamed itself in the last few years, and the speed at which it continues to evolve, is pretty astounding.

Everywhere you looked, there were little bowls of candy, free branded pens, booth babes handing out sales brochures, and all the other hallmarks of traditional American enterprise in convention mode. The air was thick with super-potent, freshly harvested business cards.

Gone are the days when triple-chambered bongs stood as the most advanced pot-related hardware for sale in commercial venues. At the Expo, a company called GrowOp Technology was demo'ing the Little Bud, a hydroponic grow room encased in a 40-foot truck trailer. Equipped with a 400 plant cloning station, carbon air scrubbers, a remote surveillance system that you can monitor via your iPhone, and a bunch of other stuff that was making burly, tattooed dudes gasp like four-year-olds ogling bright red fire engines, it retails for $49,990 and offers maximum discretion, portability, and security straight off the lot. A 53-foot version, the Big Bud, goes for $59,990 and financing is available. GrowOp co-founder Tom Del Sol told the Oakland Tribune the company has already taken 37 orders for the recently introduced units.

For those without the space to accommodate a Big Bud, there were at least two other vendors of smaller prefab grow units and also Good Green Builders, a construction company whose founders were billing it as the first licensed general contractor in the Bay Area to specialize in building custom indoor hydroponic grow rooms. There was an insurance company offering "live plant coverage," worker's compensation policies, employment practices liability protection, and various other forms of coverage for medical cannabis cultivators, dispensaries, caregivers, edible manufacturers, and delivery services. Representatives from Local Union 13, a non-profit agricultural cooperative that wants to bring health care and retirement benefits to the workers who process crops after they've been harvested, amongst other objectives, were trying to recruit new members. Oaksterdam University, an institution in Oakland, California whose curriculum includes semester-long classes in horticulture, dispensary management, cooking with cannabis, procurement and allocation, and numerous other subjects, was advertising upcoming courses. Staffers from Confidential Mediation Services were pitching their ability to resolve disputes that arise between parties who aren't exactly eager to expose the details of their business operations to the court system. "This is still an industry that's transitioning from the underground," said company founder Daniel Bornstein, a San Francisco attorney who also operates a medical marijuana dispensary. "There aren't many contracts involved."

There is, on the other hand, quite a bit of advertising. While the local alt-weeklies do a brisk trade in ads for dispensaries, collectives, doctors who specialize in writing recommendations for card-seeking patients, and home-delivery services like the Canny Bus, the industry has spawned a number of standalone publications like West Coast Leaf and West Coast Cannabis that are fat with ads too. Rosebud, which bills itself as a "hydroponics growers' lifestyle magazine," is the newest, thickest, glossiest entrant in the bunch. Its covers features Hollywood stars like Jeff Bridges, Viggo Mortensen, and Brad Pitt. Its issues run to 170 pages or more and are filled with full-page color ads for seed suppliers, high-voltage lighting controllers, organic plant nutrients, LED lighting systems, stainless steel bud trimmers, and also PETA, Chevrolet, the American Red Cross, and Cadillac.

The last time a local magazine was this thick with ads it was the dot-com era, just a few months before the monumental collapse. Then, the good times were mostly being fueled by venture capitalists puffing billions into enterprises with no real prospects of ever making a profit. This time, the good times are being fueled by consumers willing to pay $300 or more per ounce for products like Grandaddy Purple and Hindu Kush Skunk. How increased legalization—and the additional taxes and regulation that would come with it—might impact the dynamic entrepreneurism that currently informs the medical marijuana industry is hard to predict. But at the Cow Palace on Saturday, at least, the industry's future looked as bright as the interior of a mobile grow lab equipped with 1000 watt MH/HPS lights and highly reflective wall coverings.

Contributing Editor Greg Beato is a writer living in San Francisco. Read his Reason archive here.