Somerville - Fluff turns 100 this year, and the marshmallow concoction that has been smeared on a century's worth of schoolchildren's sandwiches has inspired a festival and other sticky remembrances.Every year, between 2.2 million- and 3.1 million kilograms of the sticky cream invented in suburban Boston in 1917 is produced and sold worldwide, although half the supply is bought up by New Englanders and people in upstate New York.It came of age in the 1960s, when generations of schoolchildren started clamouring for "Fluffernutter" sandwiches - still made by slathering peanut butter and Fluff between two slices of white bread.Over the past decade, fans of Fluff have been staging an annual "What the Fluff?" festival in Somerville, Massachusetts, where the American lunchbox icon was born. A fluffy look at its history:___A RECIPE CHANGES HANDSIn 1917, Montreal-born confectioner Archibald Query crafted the original recipe in his Somerville home.Query is said to have whipped up the first batches in his own kitchen before selling it door to door. Following WWI there was a sugar shortage in the US, so Query sold the recipe for $500 to two war veterans, H Allen Durkee and Fred L Mower.The recipe has stayed with Durkee Mower ever since. It's the only product the family-owned company makes.___FLUFF'S STILL THE SAME STUFFIn 1920, Durkee and Mower began producing and selling Fluff, which they first named Toot Sweet Marshmallow Fluff. The company moved to a factory in East Lynn, Massachusetts, in 1929.The original recipe hasn't changed: corn syrup, sugar syrup, dried egg whites and vanillin. And the jar's packaging is only slightly different, according to Mimi Graney, author of a forthcoming book, "Fluff: The Sticky Sweet Story of an American Icon."Fluff lovers "associate it with their own childhood and image of home," Graney says. There are competing products sold by Kraft, Solo Foods and others.___WHAT THE FLUFF?The 12th annual What the Fluff? Festival will be staged this September. It was started as a way to rejuvenate Somerville's now-trendy Union Square neighbourhood. The festival draws about 10 000 people who gather for activities including cooking and eating contests, Fluff jousting, Fluff blowing, a game called Blind Man Fluff, and concerts.Somerville residents tend to have a soft spot for Fluff. "It totally takes me back to my childhood," says Amy Hensen, a 43-year-old Somervillian.Mayor Joseph Curtatone likens the product to his community's eclectic vibe. "It's original, creative, and a little bit funky but that's why we love it," he says.___FLUFF IN SPACEUS astronaut Sunita Williams, who spent 322 days in space on two missions to the International Space Station, made Fluffernutter sandwiches on board.Williams attended high school in Needham, Massachusetts, so Fluff was a comfort food.