He started Baker Hosiery with nothing but a beat-up old knitting machine and some yarn.

NPR: Alabama Town Questions an Economy of Socks

Ullman has just co-written a book about knitting with Los Angeles yarn-store owner Mel Clark.

NPR: Tracey Ullman Takes on Knitting

Yarn bombing, also known as guerrilla knitting, is a type of street art using knitted yarn rather than paint, such as the dressing of statues in woolly hats and scarves or hanging pompoms in trees.

BBC: placard-making

Yarn bombing, also known as guerrilla knitting, is a type of street art or graffiti using items made from yarn - whether knitted, crocheted, or made into pom-poms.

BBC: Left Lion in Nottingham is 'yarn bombed'

It is an international trend called yarn bombing, guerrilla knitting or urban knitting that has spread around the world in the last decade.

BBC: Knitters transforming Newcastle's public spaces

Events include a "flash knit mob" picnic at Stratford Park Leisure Centre, with yarn bombing and other knitting activities for both the experienced and total beginner.

BBC: placard-making

Inside the hangarlike, cinder-block space, folding tables are piled with mountains of yarn, looming gear and books with titles like Knitting with Dog Hair.

FORBES: Days of Wine and Redwoods

Up to 12 colors of bright merino wool yarn are pulled from cones dangling from the ceiling into the teal-colored machines' high-speed knitting needles.

WSJ: It Ain't Rocket Science, but Sock-Making Comes Close