Over the past several hours I've had my Mint 18.2 system hang on me - twice during a Skype (64-bit) conversation, and a third time. Screen locks up, audio repeats a short pattern, no response to keyboard or mouse. After a reboot, everything seems to work again. Such a hang has not happened to me before on this system.
I've tried looking here-and-there in
/var/log, but I can't seem to find traces of the "impending doom". Where/how can I look for more clues regarding what happened?
Notes: I'm not interested in approaches like removing pieces of hardware and seeing when this behavior stops; that's a valid approach, but I'm hoping for some after-the-fact evidence to suggest what had happened.