A couple of great pictures of a hummingbird nest and babies from Scott K. in California (i.e. "Gangster Jack Russells and a couple of patterdales").
Scott thinks it's a Calliope Hummingbird (Stellula calliope).
Two Calliope Humminbirds weigh the same as one U.S. nickel (5 grams), and they make solo migrations in winter to south and south-central Mexico, making this the smallest breeding bird in North America, and the smallest long-distance avian migrant in the world!
The nest of most hummingbirds are made from spider webs with little bits of moss and lichen tossed in for bulk. Click on the pictures to enlarge. Isn't Scott a great photographer?
The smallest hummingbird egg is the Bee Bummingbird of Cuba, and you can fit 4,700 Bee Hummingbird eggs inside one Ostrich egg. Another way to think of it, is that 2 dozen chicken eggs are equivalent to one Ostrich egg, which means about 195 Bee Hummingbird eggs are equivalent to one chicken egg.