I haven't done it yet, but my plan is to build a coop this winter so we can get a few in the spring too. My coop will be in the backyard though, and hidden from the neighbors. I just hope to keep the coyotes and raccoons away from them.
I've got a pile of scrap wood and some vague ideas of what to do - I visited a couple of friends who have chickens and checked out their coops to have an idea of the important elements of design. A place to roost, some nests to lay in, and doors to make it easier to clean and get eggs. A door that can be shut and latched at night to keep the predators out, a larger enclosure so the chickens can get out a bit during the day. A water and food source.
If I'm missing something someone please tell me!