Phil Plait over at Bad Astronomy brought this to my attention and I can't resist sharing it here. Photographer Olivier Grunewald took stunning images of sulfur miners working in truly hellish conditions in the crater of Kawah Ijen volcano in Java, Indonesia.
Next to a sulfuric acid lake (pH measured at 0.5!) in the caldera are a number of vents emitting volcanic gasses like sulfur dioxide (SO2) and hydrogen sulfide (H2S). These gasses are channeled through ceramic pipes which results in the condensation of liquid sulfur as the gas cools. Deep red molten sulfur pours out of the pipes, cools to the yellow mineral and is then carried out of the area by miners in baskets. The miners work without protective equipment, obviously suffer respiratory problems, and have to hike up and down out of the volcanoes caldera twice a day. Typical miners earn the equivalent of $13 U.S. per day.
Check out the images by Grunewald - they're incredible and look like they were taken on Jupiter's moon Io!