tinyE: What we're overlooking is how stupid does someone have to be to kill someone, and then write about it on his computer? :P
Maybe it was a Go-Pro always-on livefeed transcribed in realtime to an offsite archive that was a long way away (but near a river, or a lake or whatever)?
paladin181: The BEST way to get rid of files permanently on a computer is to use a rewrite program (writes ones and zeroes over "empty" HD space), but that takes time. In a hurry? Degausing coils aren't terribly expensive and will destroy a hard drive in seconds. and by destroy, I mean wipe all data away, since it is a powerful electromagnet.
Um, where does one find a set of degausing coils?
They sound awfully expensive. What about a fridge magnet, if I spin around really, really quickly whilst standing on the drive? Or, I could tape the drive to an overhead fan and hold a handful of fridge magnets up to it!