NumWorks - The graphing calculator that makes learning math easier.

Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.

Rule of 3 Calculator - Apply the mathematical Rule of Three in an easier, faster and more practical way!

NoteCalc - Browser-based notepad built for math calculations.

PCalc - PCalc is the powerful choice for scientists, engineers, students, programmers, or indeed anybody...

Soulver - Soulver is a software application that functions as a calculator that allows you type a continuous stream of information rather than having to input data into multiple cells.