TwitterLocal tell us that Twitterlocal lets you generate an RSS or XML Feed to filter out Tweets around a certain area. Just enter a city, state, postal code, choose the range of miles you want to include, and hit the button. You’ll instantly get URLs to add to your RSS reader. Worth a try if you want to find local Tweeters!
The brainchild of Alfred Armstrong and Nikki Pilkington, Tweetake is here to allow you to back-up your followers, people you are following and Tweets with just one click.
Why bother to do this? Many reasons:
The great thing about twitter, and indeed the Internet in general, is that once something is out there and read, it’s pretty difficult to get rid of it.
So a whole generation of Internet users can grow up making idiots of themselves on twitter, and then being constantly reminded of it by articles such as this one on Inside CRM.
Particular favourites of mine from this article:
In addition, the Mistakes and Anger sections make pretty good reading.
Thanks to jcolman for this one.
You can enter your username and see how many Tweets you’ve sent - all in a pretty little graph!
Find out how you compare with the rest of the Twitterverse and then try hard not to worry that you sent 100 Tweets in the last 10 hours 
If you Tweet a lot it can take an age to load the first time, but be patient 
Follow me on Twitter - Nikki Pilkington on Twitter
Have you ever wondered who has the most followers on Twitter? Well, wonder no more.
Twitterholic ranks Twitter users in order of the amount of followers they have.
You can also see the number of Tweets they have posted, and their own URL.
At time of writing, the precious number one spot is owned by Kevin Rose, of Digg fame.
Tweetstats