It's 10pm, and the phone rings at Knock Knock Santa Rosa's headquarters. "Should I pick it up?" I ask excitedly, getting the nod. Next thing I know, I'm scribbling down an order for In-N-Out Burger: two grilled-cheese sandwiches with half-onion, one cheeseburger with no onion, two cheeseburgers with onion and extra sauce, a double burger with no tomato or cheese, an order of fries. I hear the caller turn away from the phone, surveying the room for beer.

"OK," he says, "we'll take a six-pack of Mickey's, too."

"A six-pack of Mickey's?" I repeat for clarification.

"Yeah, Mickey's," he laughs, "because we don't care about our lives."

Knock Knock Santa Rosa is a new food-delivery, beer-delivery, anything-delivery service in Sonoma County, and I'm riding along for the night to see how it works. My first question, naturally, is whether they'll deliver beer after 2am. (Alas, no.) My second question is how much it costs. For a one-stop delivery in Santa Rosa, a flat-rate charge of just $10 applies. Extra stops along the way are only $3 each. To go outside Santa Rosa, from Healdsburg to Penngrove, from Oakmont to Graton, it's $15. At Knock Knock HQ, the phone is busy, but the computer is always on as well—customers can order via email, text message, Facebook or Twitter—and in wonderful news for night owls, Knock Knock delivers until 3am.

Unlike strictly food-delivery services, Knock Knock will find, buy and deliver anything legal under the sun. Sure, they bring beer to parties. But they've also delivered rolls of stamps to a winery, patio furniture to a home, hot pizzas to a dive bar, an 89 cent roll of Rolaids to a bride at her bridal shower, filled a gas can for dirt bikes, arranged to pick up items bought on Craigslist, and shuttled countless groceries, burritos and Thai food containers all over the county. And that's just in the last two months.

With $150, a vibrant online presence and "sheer pluck," says co-founder Jinx Rhodes, the three partners who started Knock Knock earlier this year were inspired by Pink Dot in Los Angeles and the numerous late-night delivery services in San Francisco.

"But most delivery services contract with certain restaurants for a percentage markup on a really limited menu," explains partner Melissa Gordon, "and we really wanted to open it up and offer anything."

Is it those with no license or a broken car, those tired, sick, hungover, saddled with kids, disabled, elderly, too busy, too lazy—what's the most common reason, I ask, why people can't drive to buy their own stuff?

"Our demographic?" Gordon drawls. "Drunk."

Rhodes isn't so sure, though. "I thought we'd be blowing up at 1:30am for snacks and beer and stuff," she says, "but it's mostly restaurants so far, around dinnertime."

And it's restaurants tonight. I pile in the car with driver and third partner Matlock Zumsteg, just back from a chimichanga delivery, to head to In-N-Out for my call. After placing the order, I get really excited by the voyeurism of running a stranger's errands, and mention this to Zumsteg.

"Yeah, what we've compared it to, if you've ever played World of Warcraft, is those little quests you go on," he says. "You finish them and it's so satisfying." We go to a market to pick up the Mickey's, and Zumsteg texts the total to Gordon, who then texts the grand total to the customer so he can be ready when we arrive. $14.99 plus $9.13 equals $24.12. We traveled outside Santa Rosa, so it's a $15 delivery charge, plus the extra Mickey's stop is $3. Knock Knock's running a $2.50 off special tonight, so the grand total is $39.62.

Who are our mystery In-N-Out customers, I wonder? We're greeted at the door by a small barking dog and a girl in a Star Wars belt, and led into the living room where four guys crowd a big leather sofa, watching an '80s movie on a giant flat-screen TV. A-ha, I say to myself. Too engrossed in the movie to drive for food. We are saviors! I expect cheers when Zumsteg pulls the burgers and beer out of his thermal carrying box, but it turns out these guys have called Knock Knock before, and they're used to it by now.

Back at Knock Knock HQ, making shop talk like an old pro, I find that most people are overjoyed when Knock Knock knocks.

"I delivered beer to a party on A Street once," Rhodes says, "and the whole house came out on the porch to see who Knock Knock was. One girl even hugged me."

"Yeah, people love us!" Gordon agrees. "They want to take pictures of us at the door. I don't know what it is. We're a phenomenon, baby."

Place your order with Knock Knock Santa Rosa till 3am at 707.543.1110 or www.knockknocksr.com.

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