Steam Inventory Helper - Steam Inventory Helper is a free browser extension for Google Chrome that adds a big amount of new features into the Steam trade-offer system & Steam store functionality.
Kaustr - Change the way you learn
Augmented Steam - Enhanced Steam fork by IsThereAnyDeal.
Fitt - Discover health & fitness in your city
Steam Tools Hub - A set of Steam related WebApps built around trading cards, emoticons and backgrounds.
StudyQA - StudyQA is a smart search platform for programs, universities and scholarships around the world.