A little background.
My nephew is a smart 8 year old who thinks fart jokes rule, but otherwise has a great sense of humor. He loves to be tricked if the trick is clever.
Two years ago, my present to him was a Christmas Easter egg hunt. He got a hint to another egg, which led him to a third egg, and so on until he finally found the present. He loved it.
Last year, I hid a DVD for him inside the lining of the box, so he opened an "empty" box and was disappointed until we told him it must be in there somewhere. He loved that one too, and his grandma tells me he still talks/laughs about it. So I have to top it this year, or lose my rep as his smartass uncle.