Moons of all the planets in our solar system
There is a comment on the site that the Galilean Moons of Jupiter can be seen with the naked eye under dark skies. I've known people who might have eyes good enough to do that, but for the rest of us even a modest pair of binoculars is enough. To me, it's one of the funnest things you can view in the northern hemisphere without getting out more serious equipment. (Another would be the Orion nebula. If you can set the exposure on your camera, you can even photograph it, although without tracking it'll be blurry.)