My Labrador (Who is turning 6 this year i might add) Puppy runs all the time. Any excuse will do, I let him into the house, he puppy runs around me. He has an awkward encounter with one of the cats, he puppy runs around it. Meets another dog. Meets a person. The list goes on. I guess its true that lab's never grow out of the puppy stage.
Also he takes his favourite ball to bed. And when we play fetch he will only fetch his favourite ball, ignoring the lesser balls unless i get my serious on and make him get it.