BookWidgets - BookWidgets is an excellent application that let you create engaging exercises in minutes and easily share a varied variety of beautiful and fun activities with your classroom and others.

Quiver - Quiver is a notebook built for programmers.

Padlet - Visual boards for organizing anything.

SnippetsLab - SnippetsLab is an easy-to-use snippets manager.

Socrative - Socrative helps teachers engage the class with educational activities to measure and visualize...

GitHub Gist - Gist is a simple way to share snippets and pastes with others.