Add to that list:

- A depressurization event, either as a result of an accident or a botched hijacking (see https://en.wikipedia.org/wiki/Helios_Airways_Flight_522)

- Pilot suicide, with a somewhat unexpected signature (see https://en.wikipedia.org/wiki/EgyptAir_Flight_990)

Pretty much anything is possible, indeed. However, I'd recommend this post on airliners.net for a comprehensive sanity check: http://www.airliners.net/aviation-forums/general_aviation/re...