Many web/net service players are working hard to support the recovery effort, by providing critical information for affected people. I already have reported about the emergency bulletin board service by telecom carriers, so here are some other useful ones. "Google Person Finder": Simple service to upload and search whereabout of people. Available in Japanese, English, Korean, Chinese (mainland/Taiwan), Portuguese and Spanish.
"Google Crisis Response": Total portal site for related information, including government announcement, medical info, emergency bulletin board access, rolling blackout map search service, Red Cross donations and many more. Available in Japanese, English, Chinese (mainland) and Korean.
"Google/Honda/Pioneer Road Map": This is pretty amazing. The map shows the blue mark on roads where actual automobile traffic happened on the previous day, grey shows roads with no traffic, informing which roads are open for automobiles. It utilizes the GPS data uploaded from Honda Internavi Premium users' navigation devices, service operated jointly by Honda and Pioneer.
"Google Person Finder BB Photo Album": Photos of person finder bulletin boards are shared.
"OLIVE": Non-profit wiki site to share useful ideas for everyday life under the crisis, such as how to keep you warm with newspaper and stylofoam, how to cope with toilet situation, map of food distribution locations, etc. Available in Japanese, English, Korean and Chinese (mainland).
"Yahoo! power info page": Shows detailed info about rolling blackout, and provide tips to save energy.
"Anti rumor info": Blog "Ogigami-Shiki" and "Dema Chain Mail" list the typical false rumor on the net regarding the quake, and show the facts against them. There are some serious false rumors about relief operations, environmental polution etc., and some donation scams have started to pop up on the Net.
My friends over at AMN have gathered and auto-ranked the sites (utilizing data of social book marks, Facebook/Twitter mentions etc.). Some corporate sites, such as TEPCO and Tokyo Metro (subway), are included on this ranking as well.