PCalc

If you're in need of a scientific calculator for your Mac OS X, look no further than PCalc. This software is jam-packed with features that make it the ideal solution for anyone looking to do more than just basic arithmetic. With support for hexadecimal, octal and binary calculations, PCalc is perfect for anyone who needs to convert between different types of numbers.

One of the standout features of PCalc is its use of RPN mode, which allows for faster and more efficient calculations. The ability to use parentheses and programmable functions adds even more versatility to this already feature-rich calculator.

But the list of features doesn't stop there. PCalc includes an extensive set of unit conversions that make it the go-to tool for engineers, scientists, and students alike. And for those who need to access the calculator quickly and easily, there's even a Dashboard widget that can be added for maximum convenience.

All in all, if you're looking for a scientific calculator that can do it all, you won't be disappointed with PCalc. Its extensive feature set and ease of use make it a must-have tool for anyone who needs to tackle complex calculations on a regular basis.