We found a junco nest with four eggs in the tall grass in our yard.
I set up a webcam and put wire fence around the nest to keep raccoons out; here’s the live feed from the nest: http://youtube.com/nathanshields/live
I didn’t want to interfere too much, but when the four eggs had dwindled to two (snakes? rats?) I put up a makeshift wall. A chick hatched shortly thereafter.