Hidden Uncle Remus (Splash Mountain)
On www.hiddenmickeys.org there is a listing of two reports of being able to see the shadow of Uncle Remus during the ride. (On the website, it's located under Magic Kingdom funfacts, Splash Mountain.)
Supposedly, you take the giant drop. Poosh, yeah! Wet, ahh. Then you calm down, and right as you enter the mountain and you see the boat (Zip-a-dee-doo-dah Lady) with the birds celebrating on it, one of the birds shadow is not his own... rather, of Uncle Remus.