It’s a Bird, It’s a Plane, It’s Some Dude Flying a Fire Extinguisher!

I don’t believe this personally, and with two separate, perfectly set-up camera angles, (the second one being a longer version of the first) you be the judge:

These three seem way too chipper for me to believe anyone could possibly be this confident/aware of their own stupidity to set off an extinguisher in a subway car, let alone, full knowing it would actually work! Sorry to debunk your happiness there, but science pranks are cool, until you realize they’re fake.