Now, this is an original concept! Actually, this is no longer a concept, this product is already in production (in The Netherlands only, for now).
I’m talking here about a ‘balcony-on-demand’ from Dutch company called Bloomframe. This product transforms your window frame into a full-sized balcony, capable of holding a whole bunch of grown-up dudes (see photos below).
Check the action video at Bloomframe‘s web site.