I've just started working on this, so any constructive criticism is very welcome. http://media.putfile.com/nothing-to-see-here
(yeah I know I'm sort of hypnotised by the camera a bit, - let's just pretend that's part of the trick

I'm afraid the object isn't as visible as I'd like on this scaled down video. I started off with just a metal one, but it was practically invisible anyway after scaling down the video for web. I coloured it in with a black permanent marker - hopefully it shows up a bit better.
{edit} if you have the option on your browser/viewer, might be best to set the zoom to 200% or so...{/edit}