Cthree, you say, "There is some other good advice except for the advice of Paul Price who doesn't understand the difference between a bench power supply and a two prong, double insulated clock radio. That you should ignore."
I am an experienced electronic engineer and before that an appliance service technician and have been doing work with electrical gear for over 20-years.
I do know the difference and I live in a country where two wire outlets are the exception, not the rule and people do not use three-wire cords, and if they did, they would be useless because the power outlets in most houses are two wire outlets protected by GFI breakers and do not accept three-wire cords.
In any case, you assume that in a place like this that electrocutions from having two-wire outlets and using anything like a metal-cased desktop PC would be common. In fact this kind of accident is almost unheard of.
I think I stated the possible issues of a safety problem very clearly in my postings here.
I would repeat myself and point again out that having a earth grounded case to a power supply and the possibility that I might touch a live mains wire could also put me in a deadly dangerous situation. The earth ground would allow the highest current to pass through my body to the the earth ground on the power supply if I touched the power supply case and a AC hot wire in a circuit. It would not necessarily be a danger if it were ungrounded, only a few microamps of AC current from a capacitor would just likely cause me a tickle.
You must not assume that only the way you do things in your country is always the best, nor the most correct and safe.
For many years,"Mantel" radio sets were common in Australian households.
Although the Australian power system used 3 pin PE plugs for most appliances,it was common to use 2 wire "figure 8" cable on these radios,so the metal chassis was not returned to Mains Earth.
They were all transformer type power supplies,so were protected by the insulation inherent in the transformer.
There were obvious possibilities of breakdown between Active & chassis via the "ON" switch on the back of a "switchpot",which was necessarily at Mains potential.
No extreme measures were taken to insulate the controls as
was done with the AC/DC "transformerless" radios used in other countries.
Thousands of these things were used for tens of years without incident.
Occasionally,someone would bring in a "transformerless" radio from "The Old Country",& would come to grief due to it being knocked around in transit & losing some of its safety insulation,but the incidence of shocks from the locally made units was vanishingly small.
I include the above to show that I understand how the use of "2 wire" devices in a system with the Neutral earthed
somewhere in the power system is not inherently dangerous.
Back in the 1970s,I purchased a Communications receiver with a metal case & "2 wire" lead .
In my haste to "have a listen",I chucked a long wire out the window & connected an earth.causing a nice "zap" between the antenna "earth" lead & the Earthed object I connected it to.
It was apparently designed bearing in mind the US 240v system,so the RF filter circuit on the Mains input had a capacitor from each side of the incoming power to chassis.
In the USA,the chassis would have been a "virtual earth" ,but in Oz,it was the middle of a voltage divider!
I quickly fitted a 3 wire cable --not so much that I was worried about a bit of a tiny "zap",but more that the RF filter would now work,& to remove the possibility of killing something in the front end of the radio.
The old "Mantel" sets didn't have such a filter on the mains,so didn't "zap" you.
All that said,Paul,I can't help feeling that your comment on the danger of 3-wire earthed equipment is a little contrived.
Many thousands of people work with this type of equipment without incident,just as others work with 2-wire powered equipment.