I just found an interesting little application that compares the search results of Yahoo and those of Google. Once a search term is entered the application maps the common URLs of the two searches back to each other with lines and dots to show the difference between the two result sets. The result mapping functionality could be very helpful when checking your search placement for search engine optimization purposes.
The application also can compare Google China to the Google results in the United States which could be an interesting comparison with the recent news that Google is censoring China search results.
