According to the continually updated list on the the USGS web site, Japan is experiencing significant aftershocks every few hours. There have also been two serious quakes in Indonesia, measuring 6.7 on April 3, 2011, south of Java, and a 6.0 on April 5, 2011, in Kepulauan Talaud, Indonesia.
Though we don’t hear much about it on the news here, it must be terribly unnerving to the people in Japan to experience aftershocks day after day. There is no word so far on whether the Indonesian quakes are related to Japan’s great quake, but I’ll search for that information and post it when I get an answer.
Meanwhile, here is the latest list of aftershocks. For more complete information, please visit USGS (United States Geological Survey’s) web site, which lists earthquakes as they occur all over the world.