I don't have one as dramatic as yours, but a month ot so ago, I was on the bus to the office, I had my Bose headphones on and was half asleep with closed eyes.

The bus were stopped, and I suddenly noticed an acrid smell, like burning plastic.

I opened my eyes and saw the interior or the bus filled with a haze of smoke.

The doors were open and the last few other passengers were spontaneously evacuating.

So I knew I had to leave and got out in 5 sec.