"Since October 11, 2004, Mount St. Helens has been in a constant eruptive state." ... HOW eruptive, you ask? You need to see the VolcanoCam
Mount St. Helens VolcanoCam - Mount St. Helens National Volcanic Monument
Also see the section for VolcanoCam Movies...with the VolcanoCam Images Archive and the Hall of Fame Images--impressive!