Microsoft Visual Studio - Microsoft Visual Studio is an integrated development environment (IDE) from Microsoft.
GeoGebra - GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching.
IntelliJ IDEA - Capable and Ergonomic IDE for JVM
Desmos - A beautiful, innovative, and modern online graphing calculator.
Xcode - Xcode is Apple’s powerful integrated development environment for creating great apps for Mac, iPhone, and iPad. Xcode 4 includes the Xcode IDE, instruments, iOS Simulator, and the latest Mac OS X and iOS SDKs.
WolframAlpha - WolframAlpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels.