A few days ago, flight AB 7001 (Air Berlin, New York - Düsseldorf) went for a "lap of honor" around the airport.
One video can be found here.
No emergency or technical issue, it just was that airlines last ever flight on that route (they're bankrupt), and the pilot wanted to give a nice gooodbye.
Now, of course comment-sections on news regarding this are full of "experts" saying if it was ok or not. Here the question for the ACTUAL experts I can reach:
Did the pilot do anything "bad" or even dangerous, or should a quick circling of the airport be just fine as long as the pilot can actually, well, fly his airplane properly?
UPDATE: The Bundesaufsichtsamt für Flugsicherung (BAF) (German bureau for flight-safety) agrees with this page, the manoeuvre was ruled to have been legal and safe.