I saw this a month or so ago and meant to post it, but kept forgetting. So now that it's prolly been seen by everybody already, i'm finally getting around to it. The video (i was unable to embed it, but clicking on the image will take you to the You Tube page) is of a little boy who rejects several songs his dad plays for him, getting more and more upset, until finally his dad asks him what he wants to listen to and the boy chooses Zeppelin.

You can tell from his expressions that he knows the song well and is anticipating certain parts.

See also: Baby who cries whenever her dad turns off Notorious B.I.G.