Mule is a new cafe that just opened on Fourth Ave. between Boerum Hill and Park Slope. On a street filled with chop shops, laundromats, and sketchy looking restaurants, Mule is a welcome change of pace. They currently serve all sorts of coffee shop type drinks, and they have plans to add a lunch menu. The cafe has free Wi-Fi access and nice decor, with an adequate number of electrical outlets, so it's a great place to bring a laptop to do work. There's also an outdoor patio in the back.