I flew without passport or ID once, when my passport was stolen in Germany and I had to return to my country of residence, Switzerland at the time. I am a Danish citizen and I called the embassy who told me they could only get me to Denmark through the partly state owned airline Scandinavian Airlines, but I managed to talk to the the relevant people at the airport and I even managed to get a VAT refund from a jacket I bought in the airport and eventually got back to Switzerland on my scheduled flight.