twitter tools and applications are many

VArious tools and applications provided by twitter

Twitstats offers various lists of Twitter users followed by @twitstat : Top 10 today, yesterday, most engaging, most social, happy people, funny people, angry people, tired people, most replies, perfect tweets.

TwitterPoster is a visual application based on Twitter API. It provides a visual representation of the degree of influence of the Twitter users. It does not present a top list as such, but only top Twitter users are shown.

Twitter Grader gives you a grade based on the power of your Twitter profile. It also offers the list with the highest ranked Twitter users.

Twittown, the unofficial Twitter community, offers Top 150 followers, Top 150 updates and Top 150 following lists.

Twittercounter has a list called The top 100 most popular Twitter users.

Twitdir presents Top 100 followed, Top 100 updaters, Top 100 favouriters and Top 100 followers lists.

Twitterholic.com offers Top 100 lists based on Followers, Friends and Updates.