Picture from #ibc2013

Canon C500 Remote Control | Flickr - Photo Sharing! (http://www.flickr.com/photos/omegabroadcast/9734957253/in/set-72157635508127494)

Remote control seems like an understatement, or possible the wrong thing. This looks a lot more like a CCU (camera control unit). I wouldn't of thought a C500 would have one of these, but maybe there is a want to use C500s for live broadcasts and in that case, it makes sense.