Strangely, i have a design for a transformer-less PSU in the making...
My reason for not using a transformer is because to have a transformer that drops 110V and 240V down to a more usable voltage and supply the current i need would be massive and it costs >£50 each...

I'm not going to post details of the PSU because i intend on filing for international copyright.
The reason for this is because it will handle any single phase voltage, frequency and amount of noise (or noise only) you can throw at it.
It will even operate in a brown out with sustained unstable voltages as low as 24V (maybe lower).
It can also handle stepped AC, Square wave and saw tooth signals provided it is alternating...

Also, Mel is absolutely right, that AN is written for one purpose and one purpose only... TO KILL PEOPLE!