This is the extent of the 2010 Pakistan floods, shown relative to the size of the US. It would pretty much cover the Eastern Seaboard.
We’ve probably all seen the BP oil spill superimposed over a local map by now. In a similar vein, the BBC has produced visualizations of other recent disasters, including Chernobyl and Bhopal. See how many of your neighbors would be affected if these disasters came to your hometown.