"It used to be that a person working on an electrical device was safe if it was unplugged. That was the idea I got, anyhow. I started this thread so people in general would realize that that era is over."

First: the danger from stored charge has existed ever since we have had amplifiers, radios and TVs, but I guess you know that now...

Second: the computer power supply should be clearly labelled with words to the effect that you shouldn't take it apart unless you know what you are doing.

He was very unlucky to get electrocuted; in many cases you'd survive but learn not to do it again.