SkinCalc 

SkinCalc is a free calculator featuring skins and a spreadsheet interface. Skin effects include translucency and non-rectangular shapes. More than 100 skins are available from the sites listed at skincalc.com.
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Euro Calculator 

Euro Calculator is a calculator and currency converter with internet agent that collects daily rates. Features include a spreadsheet interface and translucent skins. Calculator and euro conversion functionality never expire (freeware).
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WorldCalc 

WorldCalc is a calculator and currency converter with daily exchange rate updates provided by Cloanto, a leader in currency services. Includes a spreadsheet interface and translucent skins. The unregistered version displays an advertising banner.
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