I don't see why a simple power monitor/logger gadget can't be battery powered, or more precisely, line powered with battery power to carry it over the hopefully rare occasions when the line power fails, preserving the already logged data and keeping its internal clock running. We're talking about logging mostly short losses of voltage in household electric service that's mostly on -- and battery backup should keep a simple logger gadget running for days if not months.
In my household the built-in wall oven apparently has a built-in battery; it's clock and other settings will still be valid after a 20 minute outage. Some electric clocks and most of the cordless and cell phones will retain settings for a day or more; and of course all the laptop computers for much longer. The thermostats for the HVAC ditto.
The microwave oven's clock display, however, is flashing "==12.00==" over and over after even a sub-second glitch, as are many other electric clocks. The coffee maker with a built-in auto-start feature to make coffee just before 6:00 am each morning has lost all its settings -- but comes back up with its heating element still on if it was on when the power failed; lovely safety feature, that.
Most annoying is the expensive, highly touted Bose radio: it loses all its settings -- time, station presets, etc -- on even the slightest power glitch. (Lots of other things not to like about this overpriced radio as well -- DON'T BUY BOSE is my recommendation.)
Sounds like I'll have to look at this -- but I don't really want UPS, especially for the household appliances, and would initially just like to assemble some data on how badly PG&E is really doing.
[TELECOM Digest Editor's Note: Now wait a minute! I have a Bose radio and that does not happen. The radio has a battery compartment which keeps everything in place. The battery does _not_ continue to play the radio, but when our power goes out here, I do not have to reset the clock or the presets, etc. Do you have a battery in your Bose radio? PAT]