I came across this APC product page for Microsol Isolator Modules, which purportedly provide "safe power in places with poor or nonexistent grounding." The unit is meant for Brazil, so it won't work in my case, but I'm wondering what the underlying technology or implementation is and if it provides some kind of "virtual ground" to simulate an actual ground.

I live in Argentina, where most houses are built out of concrete and many are old enough not to have ground wires running through the walls. I live in a second story apartment with no ground wires, no radiators or accessible cold water pipes. From what I can tell, running a ground wire through the wall would entail tearing down a significant portion of the walls and would be quite costly. The climate where I'm at is similar to Arizona, so I'm not even sure I could get to the water table if, in the unlikely event that the landlord and the downstairs neighbors were to give me permission to place a grounding rod in their interior garden below.

If I used a bootleg ground in combination with a GFCI outlet, would the GFCI kill the neutral end of the socket and prevent current from being pushed from neutral to "ground" to my equipment? Ground is tied to neutral at the service entrance but nowhere in the walls. Is there some other kind of second circuit breaker or box I could install in my room with a computer and ups that would be more like what's at the service entrance and less like a bootleg ground?

There is a metal gas pipe outside of my window. How dangerous would that be to use as a ground?

I have a door in my bedroom that the landlord has sealed off with duct tape because it opens to a staircase that leads down to the neighbor's garden. If I were to take the door out and seal it with concrete, sticking rebar in the wet cement, could I build an "Ufer" ground or does that have to be under actual ground?

Would it be better than sticking a nail in the wall and calling it "ground." This slightly absurd sounding "method" gives me a reading of 300 Ohms from neutral and a difference of about 15 volts when connected to hot (220 volts), compared to a hot-neutral reading (235 volts).

Electricity in Argentina is single phase, ~220v, 50Hz. We use a mix of older style European two prong cylindrical outlets and newer, three prong, Chinese/Australian style plugs (with neutral and hot reversed). Getting shocked by refrigerators when barefoot is almost a given here and almost everyone uses voltage regulators to deal with power irregularities. When testing outlets at home, I can seen the voltage spiking to 1000 volts on my multimeter every few seconds, but only on some outlets (all are single-phase, 220v). What other kinds of voltage regulators will work without ground? Most of my electronics are dual voltage, so ideas including transformers that step down to 110-125v would be fine too.

Can I hook a voltage regulator up to a GFCI outlet and then hook a UPS into the voltage regulator to deal with nuisance trips from the GFCI and avoid hard drive failure? Can I still get surge protection without ground?

Other stupid grounding ideas: There's a grid of galvanized steel cables, spaced about one foot apart and set into the concrete walls outside which are there to hold up a grapevine. The cables are about the same gauge as a fence, maybe slighly thicker than the copper electrical wires in the wall. If I get good readings on the multimeter, can I use that as a ground? Will it electrocute the neighbor's cats who climb up on the vines or burn the grapevine? What would "good readings" (volts/ohms) be from the multimeter?