Hello, this posting is not purely related to math. I stumbled on this site which has an impressive set of constructions in lego, one of them has some striking patterns : http://remocable.blogspot.com/2011/08/blog-post.html some other inventions are really cool, http://remocable.blogspot.com/2011/08/old-time-inventions-genius-is-one.html and many other contraptions. bonne journée and best regards, Simon Plouffe