Code Duet - Finding a partner for pair-programming in 5 minutes
Quizzes for Pages - Quizzes for Pages is an application to create and share quizzes on your Facebook Page.
Whale - Video Q&A with influencers and experts 🐳
Outgrow - Enabling marketers boost conversion with interactive, beautiful & viral quizzes/calculators.
Codewell.cc - Improve your HTML and CSS skills by practicing on real world design templates.
Poll Everywhere - Audience response system that uses mobile phones, twitter, and the web. Responses are displayed in real-time on gorgeous charts in PowerPoint, Keynote, or web browser.