The Great Quake

On April 18th, 1906, a massive earthquake rattled the San Francisco Bay Area for nearly an entire minute followed by fires which left the city in ruins and an estimated 3,000 people dead. There are many great archival resources available online to see and explore, as well as many local Bay Area events.

 
As Gary points out, Ask.com's Smart Answers have many resources for both the 100 year anniversary of this tragic event, as well as more contemporary earthquake-related features; including a near real-time list of current earthquakes, earthquakes by area (if applicable), and even another on earthquake preparedness.
 
As we look back at this destruction with awe and wonder, it is important to also think of the future. According to the U.S. Geological Survey, there is "a 62% probability that at least one earthquake of magnitude 6.7 or greater will occur on a known or unknown San Francisco Bay region fault before 2032". Recent natural disasters such as last year's earthquake in Pakistan or Hurricane Katrina should serve to reminds us to prepare for the future as best we can.