Tambora, Indonesia
This news came from a few weeks ago, but one of the most famous volcanoes on Earth is rumbling. For the second time in the last three years, the CVGHM (Indonesia's volcano monitoring agency) raised the alert at Tambora to level 2 after an increase was noted in earthquakes occurring under the caldera. Now, this doesn't mean an eruption is likely to happen any time soon -- as we saw the last time they raised the alert status, no eruption followed. However, it does remind us that Tambora is an active volcano in a densely populated country.
Image: Paul Hessels / Flickr, taken on June 14, 2008.