Calc98 5

the author of this app says:

Calc98 is a scientific and financial calculator program for your Pocket PC. Suitable for the scientific, engineering, medical and teaching professions, this free program offers financial and statistical functions that go above and beyond other programs like it. It contains a comprehensive set of conversions, constants and physical property data, a built-in periodic table of the elements, number base conversions, vectors, matrices and complex numbers. This could very possibly be the only calculator you need!