We never really appreciate the conveniences that modern technology has afforded us until the "grid" goes down and we are left sitting in the dark trying to squeeze a few more minutes from our iPod's almost-dead battery. In yesterday's edition of his weekly column, the Wall Street Journal's Walt Mossberg test drives several devices that either work during a power outage, or provide power to AC-dependent electronics. First off, he (and his assistant Katie, who is mentioned many times, lest we underestimate her import) puts two hand-crank radios head-to-head and evaluates their effectiveness during an emergency. Coming out on top is the Eton (really Grundig) FR300 Multi-Purpose Radio, which manages to pack in AM, FM, weather band, and two TV audio feeds, along with a cellphone charging attachment, small flashlight, and siren. The FR300 runs on batteries as well as musclepower, although only a minimal amount of cranking (30 seconds) provides over a half-hour of usage. Mossberg (and Katie, don't forget Katie) also looks at the Freeplay Eyemax Weather Band Radio, which one-ups the Eton with its solar panel, but falls short in the display and ease-of-use categories, all at twenty bucks more than its $50 rival. Finally, the dynamic duo rereview the disposable Cellboost electronics chargers, and once again, decide that they work. It should be noted that none of these products will do you much good if the communications infrastructure goes down along with the power grid; in that case, your best emergency "tool" may well be a sawed-off shotgun, pitchfork, or similar looter-deterrent.