Mag-Lite: Ontario-based Mag Instruments specializes in sleek, durable, high-quality flashlights. All of their products are designed in California, and manufactured by USA workers in USA factories.
SureFire: I have mixed feelings about including Fountain Valley-based SureFire on this list. They make a host of useful products, including handheld flashlights, headlamps, and even lights you can wear on your wrist. And the quality of their offerings looks good. SureFire markets themselves, however, as gun nuts serving gun nuts -- everything they sell was designed with shooting in mind.