Back in the mid-70's (when I was but a young-un), we lived in a large block of apartments (on the 7th floor). This block faced a couple of other similar apartment blocks.
One night when my mum was out and the kids were in bed, my dad and a couple of buddies decided they were going to watch a 'dutch' movie they had acquired.
Now, this was back in the days before VCR's and DVD's.
So, they set up the projector.
Not having a wall large enough to project the movie on to, they hung a large white bedsheet in front of the balcony windows.
Then, they grabbed a few cold beers and sat down to watch...
An hour or so later, when the movie was finishing, they heard a light smattering of applause...
They took down the sheet to reveal a significant number of people on the balconies of the other apartment blocks applauding their night-time show.