On my night rental (sorry, self-fly-hire) checkout the instructor had me turn off all my lights in a hover at a dark corner of the airport and do some pickups and set downs many, many moons ago.
Also had a dude in a Blackhawk come on the radio (while I was doing my night currency circuits) and ask the airport if they'd turn off all the lights so he could do an NVG approach. That was kinda cool.
Had a couple of birds fly under my blades while on an approach one night. They didn't have lights on either.
