SpeQ Mathematics - SpeQ is a small, extensive mathematics program with a simple, intuitive interface.

PyScripter - PyScripter is a free and open-source Python Integrated Development Environment (IDE) created with...

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

Visual Studio Code - Build and debug modern web and cloud applications, by Microsoft

NumWorks - The graphing calculator that makes learning math easier.

Sublime Text - Sublime Text is a sophisticated text editor for code, html and prose - any kind of text file. You'll love the slick user interface and extraordinary features. Fully customizable with macros, and syntax highlighting for most major languages.