I got this via email from a friend, impressive.
Impressive aerial 'dance' performed at the opening ceremony of the 2014 Youth Olympic Games in Nanjing. Synchronising at its best! There were 500 performers. Unsure whether this included those on the ground who made up the moving circle which complemented the aerial act and those manipulating the ropes. Nevertheless, without the perfect timing and synchronising of everyone, this act could not be as flawless as it was on the night. (Suspect that mathematicians and not just choreographers were involved.)