Years ago, I heard that a small part of the older section of Bogota (capital city of Colombia) had 150 volts. However the nominal voltage in the rest of the city is 120 at 60 hertz.
According to my grandmother, Cali used to be slightly lower (nominal 110V), but according to that city's utility company, the nominal voltage there is also 120...so who knows. When she moved to Bogota, she took her large Philips multi-volt radio and remembers turning the voltage selector knob to 125 (from the 115 spot it was set for).
I don't know if this 150 volt system still exists. Probably not.
As far as 127 volts, I've heard it's the nominal voltage in Mexico...or at least was. Wiring devices and appliances I see imported from Mexico are rated either 125 or 127 volts at x-amps.
I wonder if that's also the case in the USA/Mexico border. Can anyone living in San Ysidro or such border towns give us a voltage reading at their normal wall sockets?
Maybe next time I go visit Tijuana or if I go to Cancun, I'll take a small volt-meter with me. Just for kicks.
Local voltage in New York City is about 118. I've heard of some parts of the USA having voltages as high as 125 or as low as 105.