Mount St. Helens-Fall 2004
Links of interest for monitoring current activity:

Recent images of Mount St. Helens, including monitoring activities
Seismic monitoring of Mount St. Helens
Current Activity updates
Mount St. Helens webcam
Explanation of USGS warning scheme for volcanic hazards
Page with links to background on Mount St. Helens

KIRO TV page-good background info, updated very frequently