Abstract: Innovations in sensor technology, software, optical coatings, and mass production can be coupled to allow powerful wide-field imaging telescopes to be constructed unbelievably quickly and relatively inexpensively. The Dragonfly Telephoto Array (Dragonfly for short) is an example of this kind of thinking, and over the past few years it has ignited interest in the low surface brightness Universe. In this talk I will describe how Dragonfly works and present new results on stellar halos, ultra-diffuse galaxies, and on galaxies lacking dark matter. I will also describe how we are turning Dragonfly into an ultra-sensitive emission line mapper. Our goal is to allow the circumgalactic medium of galaxies to be imaged directly, side-stepping all that tedious mucking about with quasar absorption lines, and probing galactic feedback in a straightforward way.