If you don’t know about Krakatoa, you should read about it. In 1927, in the Krakatoai group, a new volcano arose from the sea, and then went quiet. They called it Anak Krakatau.
In April of 2008, it started erupting again, and is still erupting. Here’s a picture from today’s APOD.
Interestingly enough I saw a show on the science channel or national geographic the other night about this. They were showing how islands in that chain develope. There was a major eruption of Krakatoa in the late 1800 that devistated the area and effected the whole worlds climate.