I've watched a documentary about this before, where they are saying that these are being done by group of students, they plan and do the whole complicated designs overnight using a long similar to plywood as a sketcher (they put these as their shoes and attach as a string)...i will see if i can find this documentary online...

[img_assist|nid=12867|link=none|align=left|width=|height=0]Nothing in life is to be feared. It is only to be understood.