Microsoft has filed a patent claim for sparklines in Excel:

http://sparklines-excel.blogspot.com/2009/11/united-states-patent-application.html

[…]

Further discussion is found at

http://blogs.law.harvard.edu/philg/2009/11/19/microsoft-puts-edward-tuftes-sparklines-into-excel/

What should I do?

via www.edwardtufte.com