Google announced today that it has partnered with the U.S. Geological Survey (USGS) to add real-time earthquake search results. Simply type in “earthquake” and results will yield the most recent tremors around the world.
Type in “earthquake California” and you’ll get a listing of activity in the area. Here’s a snapshot (which also includes my Twitter add-on results):

Here are some other cool Google search functions, while I’m at it.
Check out more search functions on Google’s Search Features page.