About eight years ago, a hummingbird build a nest on the top of some wind chimes. The nest was about the size of a man's thumb and the eggs about the size of the tip of your little finger.
To my initial delight, she had two little ones. I couldn't believe that I could get so close to them for these shots, but the parents didn't have any trouble with us - the cats were a different matter.
Then came the 'nectar' poop and the back porch was unusable for a month. Still, it was worth it to watch these little guys grow and fly off.
For scale - the metal loop holding the chimes up is about 2 1/2 inches long.