You are a few pickles short of a sandwich here! : )
>To be AC you have to have a return and that is not present. IE: The neutral wire >in your house wiring.
If you have figured out some kind of DC circuit that does not require a "return", what do you call the ground side of the circuit?
Take a coil, ground one end of it, swing a magnet close to it and the open end will swing an equal amount positive and negative as the magnet passes. You can half wave rectify this with a single diode but half of the power will be lost.
Household current is not 3 phase. The wires coming into your house provide 2 110v lines and a neutral. You get 220 by connecting between the two 100 volt lines, seems to me this is 2 phases, 180 apart. 3 phase would give you about 207v between any two phases..
You are right about home electronics, however, if they need significant power they use an isolation transformer to eliminate the ground, then a full wave rectifier.
If you can find someone with an oscilloscope, look at your peds power, you will be enlightened.