With TwitterFriends you can:
- Find out the hidden network of Twitter contacts that are really relevant for you.
- Visualize the network of your relevant contacts and their contacts
- See who of your Twitter friends are online this very moment
- Read some stats about your Twitter account
- Take a look at the most conversational Twitterers or those who are posting the most links
An example page:

Traffic rankings are sourced from multiple sources, if available, for the Twitter application. This includes Alexa, and Compete rankings.