10 Twitter Apps - How many do you use?

Just found this great list of Twitter apps for productivity in managing my Twitter accounts. I am ONLY using 6 of these 10... how about you?

The article starts:

Are you still looking for the best Twitter services and utilities that are able to enhance your tweeting experience and bring more value to it? Look no more for today we will be sharing with you the top 10 Twitter utilities available on the web:

1. bit.ly: The best URL shortner around used by various Twitter applications directly or to leverage their bookmarklets.
2. Ping.fm: A highly valuable service that allows you to publish your updates to many social networks simultaneously.
3. Visibli: Optimizing engagement means sharing great content– even if it isn’t your own. The Engagement Bar shows your brand above each linked page to keep you top-of-mind. Also has analytics.
4. Tweepi: A great Twitter management tools with stats which allows you to follow, flush, reciprocate and clean up your Twitter account based on users’ activity, engagement, retweets and so on.
5. Twitter Split: An interesting tool you can install to allow you to track links in tweets you post.
6. TrueTwit: A Twitter validation tool that helps automate some key services.
7. Twit Longer: A simple tool which allows you to send longer Tweets.
8. Twitter Keys: Blog post with a variety of little icons and images you can add into your tweets to make them more fun and expressive.
9. Follow Friday Helper:  Let’s you easily build thank you & other messages to people who mention, RT, etc. you.
10. TwimeMachine: An easy way  to see all your past Tweets.