Got an earthquake of magnitude 4 afternoon. I felt a weak shaking and gradually it became strong. Of cause I remembered about a rumor in a prompt, but I knew it wouldn't last longer than 30 seconds.
It's been told that a strong earthquake will happend in Tokyo for years since I was a little kid. I took part in a fire/earthquake drill at school and also at work. My family have already chooen a place to meet up if we cannot get in touch with one another after the earthquake. Probably we won't be able to use even a mobile in a confusion.
There is no help for an act of God, but all we can do is to prepare some foods or water for it and I recommend you, if you live far away from your family, that you'll ask your nighbours or friends a favor to contact your family just in case something occures to you.