My knowledge of earthquakes is sorely lacking. I remember taking a physical science class in 8th grade, and learning all about how tectonic plates cause them--they stretch apart and then when the pressure becomes too much they'll snap back together and there's your earthquake. The more pressure, the stronger the snap, the bigger the earthquake. But my personal experience...well I've never been in an earthquake.
However, I think most of us probably know by now that Japan was just struck by a huge earthquake.
I began following the news about 3am my time (it was afternoon there) and listened, horrified and saddened by what was happening there. I went to bed at 5:30, knowing I needed sleep, but I'm up again now and back listening to what's happening from the same live broadcast source I was using earlier. If you're interested, it's here: http://yokosonews.com/live/. (I'm sure that link won't work in the future, but for now...)
Airports are shut down right now, flights canceled, some areas completely devastated. From what I've heard, if you were planning a trip you should definitely check on your area before you decide whether or not to cancel. If you were heading to Tokyo, put it off. Sendai, definitely cancel--Sendai is in terrible, terrible shape. However, if you're going to Osaka or Kyoto, you should be fine. Katz (the broadcaster, for anyone who didn't follow the link) says if you're going to somewhere that's in pretty good condition, to definitely still come, to cheer them up. I couldn't help smile when he said that.
Anyway.
I'd just like to say that we all need to keep the Japanese people in our thoughts, our prayers (for those of us who are religious).
That is all.