From Institute of Mathematics and Statistics:
CompactCalc is an enhanced scientific calculator for Windows with an expression editor. It embodies generic floating-point routines, hyperbolic and transcendental routines. Its underling implementation encompasses high precision, sturdiness and multi-functionality. With the brilliant designs and powerful features of CompactCalc, you can bring spectacular results to your calculating routines. You can build linear, polynomial and nonlinear equation set. You are not limited by the size or the complexity of your mathematical expressions. CompactCalc has almost hundred of physical and mathematical constants built in, which can be easily accessed and used in calculations. No longer do you have to search the physic textbook for that common physical constant data.