TTCalc has been reviewed by
TTCalc is a mathematical bignum calculator that features lots of functions for converting between degrees and radians, trig and inverse trigonometric functions, arithmetical functions, hyperbolic and inverse hyperbolic functions, and custom functions (these are functions that you can define yourself). You can use the application to perform a large variety of calculations, from simple to quite complex ones.
TTCalc portable is a nice advanced Mathematical calculator written by Tomasz Sowa. Available in both English and Polish languages TTCalc is so simple to navigate and very easy to use. TTCalc contains hyperbolic and trigonometric functions amongst many more. The portable calculator can do conversions as well. Best of all it is tiny and can easily fit on the smallest of USB Flash Pen Drives.