Google have made available imagery from NASA’s MODIS as an overlay for Google Earth, which currently shows the extent of the Gulf of Mexico oil spill through April 29. They have also posted radar images from ESA’s ENVISAT in this KML file.
Gulf of Mexico Oil Spill Map
Google's Crisis Response Team have also created a Google Map to show the extent of the Gulf of Mexico oil spill. The map includes a number of layers that can be selected to view on the map.
The layers include the images from NASA'a Modis and ESA's ENVISAT. You can also view an Oil Slick Overview from the U.S. Coast Guard, the current spill extent from the State of Louisiana, the observed spill from the State of Louisiana, fishing closures, locations of the booms and points of interest.
Via: Official Google Blog