Mayon in the Philippines, taken in 2007
There has been a lot of waiting over the summer to see if Mayon in the Philippines was going to begin a new eruption sequence. This morning, the volcano had its first "eruption" since August 2008, producing a very small (~700 m / 2000 foot) ash-and-gas column that drifted to the southwest. PHIVOLCS reports that the plume had very minimal ash, but it is still worth noting. No new evacuations were called, but the 6-km "danger zone" and 7-8-km "extended danger zone" are still in effect.
Mayon is one of the most active volcanoes in the Philippines, erupting every few years, typically in small VEI 0-1 explosive events - usually starting as phreatic (water-related) explosions. Some recent eruptions, most notably in 2006, produced lava flows and pyroclastic flows as well, while the 1984 eruption rated a VEI 3 with lava and pyroclastic flows along with generation of some lahars.