ifttt (if this then that) allows you to set up triggers on a wide range of networks including Facebook, Twitter, email, weather, etc., and actions to take when those occur.
News.me scans your Twitter feed and populates a list of the best stories.
TwitDo is an automated "to do" list that is controlled via Twitter.
Photorank.me is like Klout for photos. It rates a user based on their photo-sharing exposure.
RockMelt is a Chromium-based web browser that integrates social media systems, such as Facebook and Twitter.
Klout assigns a popularity 'klout score' to your Twitter username, based on your followers and other facets.
Twuration calculates how many days you have been a Twitter member and the number of times you tweet per day, on average.
Twitter Grader is a free tool that allows you to check the power of your twitter profile compared to millions of other users that have been graded.
TweetingSince allows you to enter your Twitter username and see which other usernames were created on the same day as yours.
WeFollow is a Twitter directory and search site.
