The NY Times writes on the Chewing Gum Art of Ben Wilson. He developed a technique in which he softens the gum with a blowtorch, sprays it with lacquer and then applies three coats of acrylic enamel. He uses tiny brushes, quick-drying his work with a lighter as he goes along, and then seals it with clear lacquer. Each painting takes between a few hours and a few days, and can last several years if the conditions are right. More images on Flickr here.