It's a rare kind of person that is so bored by roller coasters that they have to find another way to make the experience interesting, but they're out there. There's a whole bunch of people who like to sneak various props and objects onto rollercoasters so that, at the moment the camera goes *click*, they can strike the ultimate pose.
So check 'em out. Yep, they're all here. Most of 'em, anyway - the photo of the guy who snuck a katana on to Splash Mountain is a bit too grizzly for this time of day.