Projector test
Some time in the late 90s our team was tasked with testing a brand new projector with VGA input, and after a few successful tests in our darkened office we became curious as to how far the projection could reach. With a whole web server full of pr0n available, we picked a movie at random and projected it onto the white outer wall of the church opposite - the picture was bright enough for details, so the test took less than a minute.
Luckily that wall was on the backside of the church, so we were the only witnesses.
Anon to protect the others involved.