Show duplicate cell values in an Excel document?

Question

I have an Excel document with two columns of data. I'd like to quickly see what values in column A exist in column B.

For example, imagine column A had the list of US President last names and column B had a list of the names of the states in the United States.

I'd like to see that the value "Washington" exists in both columns A and B.

Thanks

Answer 1

With Excel 2010:

For 2003: http://www.techrepublic.com/blog/msoffice/how-to-find-duplicates-in-excel/842