I wanted to do a spectator level like a stereogram, that would be cool to see it in motion with physics , but it needs structures who do exactly the same in synchro...
It need copy-paste function but I managed a start with the boundaries tip to make really straights line and use them like a grid.
here is a page about stereogram if you don't know how to watch it: http://en.wikipedia.org/wiki/Stereogram