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.
TTCalc Portable - Calculator Screenshot:
Authors Website: Project Page
License: Open Source
Download: Download the portable version HERE