If it was my home ...
At first I wasn't going to post this Gulf of Mexico oil spill visualiser because it seemed to me to just replicate Paul Rademacher's How Big is the Gulf of Mexico Oil Spill? map. However, because I have been inundated with requests to post the map, I've had a second look and been convinced that the map is more than worth a look.
Like Paul's map 'If it was my home ...' lets you compare the size of the oil spill to any location on Earth. Using Google Maps you can move an overlay of the oil spill to any location, which is a very effective tool in visualising the share scale of the oil spill.
A cool feature of 'If it was my home' is that it detects your location and automatically centres the oil slick over your current location. If you want to visualise the oil slick at different locations you can also move the overlay to anywhere your want.