The invincible human moth is a great piece of speculative sci-fi. It’s about a magician who uses the gedankenexperiment of quantum suicide to perform impossible tricks: he kills himself (or has someone murder him) if the trick doesn’t work. Thus, his consciousness only experiences those worlds where all of his tricks work.
Of course, this also means he can never die (roughly speaking).
A really good concept, executed chillingly well.