Windows 7  gave Calculator a fresh look and new features, including new Programmer and Statistics modes. Unit conversion translates Celsius to Fahrenheit, ounces to grams, and joules to BTUs. Handy calculation templates can help you compute stuff like fuel economy and auto lease payments.

This default calculator goes above and beyond the brick on your desk by including unit conversions, date calculations, and a neat new set of "templates" that let you do things like figure out gas mileage, hourly wages, mortgage payments, leases, and more. Check out some of the calculator goodness in the Windows 7 Preview.

Find More - http://www.freewindowstips.com/2010/09/28/windows-7-calculater/