Labor Day is now much more than a celebration of the labor movement and its contributions to the social and economic achievements of American workers. Like most federal holidays, it’s has been transformed into shopping bonanza — a chance to take home must-have hardware on the cheap. We’re talking about clothing, laptops, mattresses, smartphones, and televisions, and everything in between. You’ll need to act fast when the time comes, though: Unlike Cyber Week, the best Labor Day sales only last for one day. When they’re over, they’re over.