A Minnesota anglnig products company that sells most of its output in a two-month window is about to double the size of its offices, because business is booming. Clam Corporation, of Medina, has been doing so well from ice-fishing accessories that it is about to move to new premises in Rogers with 150,000 sq ft of space. The largest US maker of portable ice-fishing shelters, apparel and accessories, Clam employs more than 50 permanent and temporary employees between October and December, as well as working with more than 50 ice-fishing pros. More than two-thirds of its sales are related to winter angling and its annual sales have consistently grown 10-15 % in recent years. Full story here.