Where: San Francisco, California

In this uniquely San Francisco 12K—that’s roughly 7.5 miles—a handful of world-class runners mix (but only briefly) with 50,000 weekend warriors, walkers and devil-may-care costumed participants. With twice that number of spectators and live bands interspersed along the route, it’s a rollicking party that spans the city from San Francisco Bay to the Pacific Ocean. Next Race: May 2014

baytobreakers.com

Where: Medoc wine region, France

This run is more moveable feast than serious marathon. Costumed competitors weave their way through storybook chateaux and vineyards, stopping to sip some of the world’s finest wines (Chateau Lafite Rothschild and Château Grand Puy Lacoste are among them) at 20-plus drinking stations and sample rich local delicacies like foie gras, oysters, sausage, steak, cheese and fruit. It’s an entirely French approach to distance running, and it only gets easier with every glass of red. Vive la France! Next Race: September 2013

marathondumedoc.com

Where: Boston, Massachusetts

The urban take on Alaska’s famed Iditarod replaces sled dogs with people, snow gear with wacky costumes and sleds with shopping carts. It’s no 1,000-mile epic, but there’s definitely a challenge to finding the five checkpoint bars, participating in secret challenges (which, in the past, have included pole dancing and bowling), chugging beers and running in the cold of a New England March day, all the while filling your cart with non-perishable goods for a food drive. Next Race: March 2014

bostonurbaniditarod.com

Where: Nationwide

Participants in this 5K start dressed in head-to-toe white, but finish looking as vivid and paint-splattered as a Jackson Pollock painting. At regular intervals along the route, volunteers douse runners with colored powder (yellow, blue, green pink and—at the finish line—a “color extravaganza”). It’s all about fun and positive energy at this race in which more than 60 percent of entrants are first-timers. Next Race: August 2013

thecolorrun.com

Where: Raleigh, North Carolina

This nearly decade-old race was one of the first to combine binge-eating with running (funny it took so long to think of!). Nearly 8,000 runners cruise 2.5 miles out on the course, eat a dozen original glazed doughnuts (glad it’s not chocolate custard-filled), then waddle, walk or crawl back to the starting line at North Carolina State University’s bell tower. It’s no doubt, as organizers claim, “a test of physical fitness and gastrointestinal fortitude.” Next Race: February 2014

krispykremechallenge.com

Where: Nationwide

This 5K race puts a jump in your step by unleashing hordes of blood-thirsty, brain-hungry zombies on the course, which is littered with man-made and natural obstacles. Focus on the running, and give a wide berth to anyone with a noticeable lurch wearing blood-wicking performance wear (rumor has it you can save loads of money on registration if you have a taste for brain). If you make it to the finish, toast your fellow survivors at an “apocalypse party” with beer, food, games and DJ music. Next Race: August 2013

runforyourlives.com

Where: Nationwide

With high-energy DJ mixes blasting and bright lights flashing over the course, this fun run could just as well be called a 5K rave. Neon-bedecked runners (and, yes, dancers) make for a living light show that ends with a finish-line dance party. Next Race: August 2013

electricrun.com

Where: Dallas, Texas

Before gorging yourself on turkey, why not dress up like one and burn a bunch of calories? That’s the thinking behind the Turkey Trot, an annual Thanksgiving morning tradition in hundreds of cities across America. While you’ll always find your fair share of runners dressed as gobblers, Pilgrims and Natives Americans, it was at the 2011 Dallas event that they set the world record for biggest turkey dressing—661 people wore turkey costumes for the big day. Next Race: November 2013

thetrot.org

Where: Nationwide

Go nuts at "America's Sweet Race," which takes the idea of chocolate milk as a recovery drink to the next level, offering finishers rich Ghirardelli hot cocoa, chocolate fondue and other chocolaty treats.

hotchocolate15k.com

Where: College campuses nationwide

“Bare because we care” is the motto of this fun run that challenges college kids on 70 campuses across the nation to strip down to their underwear and give the clothes off their backs to charity (as if they needed an excuse). The clothes they ditch at the starting line—prior to a near-streak across the quad—are donated to local shelters (200,000 pounds so far, and counting).

undierun.com

Where: Ann Arbor, Michigan

Though it sounds like an April Fool’s joke, this fun run is 100% serious about fueling runners with mountains of Twinkies—both store-bought and homemade—before, during and after the run. There are plenty of calories, to be sure, but the breakfast of champions this is not. Next Race: April 2014

a2a3.org

Where: Cincinnati, Ohio

The Run Like Hell is a 5K costume race that winds through 70-acre Walnut Hills Cemetery after dark (creepy!) before turning into a full-fledged monster mash at the finish line, complete with food, beer and live music. Next Race: October 2013

cincyrunlikehell.com

Where: New York, New York

The gut-busting challenge of this fun run is to complete 2.25 miles while scarfing three slices of New York’s finest thin-crust pizza. Last year’s male winner, triathlete Jonathan Blyer, followed a strict training regimen of chewing soda crackers without water for three weeks in advance of the race. Brutal. Next Race: September 2013

nycpizzarun.com