CM's have hidden some of Huck Finn's paintbrushes around Tom Sawyer Island. If you find one, pick it up, and take it to a CM. They will take the paintbrush from you, but give you a front of the line pass for Splash Mt. or Big Thunder Mt.
I think that pass is good for your whole party.
Last Dec. I tried looking for one in the afternoon. I didn't find one.