The crater of Poas (Costa Rica) always smoking.
Poas - this really is the colour of its acid lake.
Seeing this eruption on Aranal was (and still is) the most
amazing sight I've ever witnessed - the noise, the earth shaking,
an indescribable experience.
Click picture for video - 938KB 
Val del Bove on Mount Etna 1990
Val del Bove in 1992 after the major eruption
which nearly destroyed the town of Zaffarana.
The bottom of the valley rose by nearly 30 metres
Some other Volcano information can be found at..
http://volcano.und.nodak.edu/vwdocs/volc_images/img_poas1.html and
http://volcano.und.nodak.edu/vw.html