Look lads (esp mr titanic1912)- if you want a fast way our when doomsday comes may I respectfully recommend a large bottle (or several if you're a hardened drinker) of Remy Martin Cognac.
I guarantee that if you drink enough of it no dinosaur/meteor/alien/volcano/earthquake/mutant star goat/darthvader/black hole/higgs bosun will be noticable.
What a way to go- Cognac'd to death