Rufus By Jtanza - Rufus is a free, open-source web based RSS reader, designed to be both simple and fast.
Listr - Listr lets you explore some of the best lists on Twitter, curated across your favorite categories.
FamousFix - Formally known as WhosDatedWho
Refined Twitter - A browser extension that improves the Twitter experience
Muckerty - Find out the relationship between people, organizations, and companies in the news.
Vicariously.io - Create Twitter lists based on the follows of other users