Outgrow - Enabling marketers boost conversion with interactive, beautiful & viral quizzes/calculators.
hackattic - No nonsense, real world programming challenges
Quizzes for Pages - Quizzes for Pages is an application to create and share quizzes on your Facebook Page.
HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.
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.
Takehome - Effective and humane coding challenges for candidates