I am a fan of most things Twitter related, I love the the sheer simplicity of the app. And, just to make this easier, here are 9 Adobe Air Apps for Twitter:
Toro for Twitter
Download:Toro for Twitter Download.
Developer URL: Christopher Hayen.
Spaz – an award-winning Twitter client
Download:Spaz Download.
Developer URL: Funkatron.
TweetDeck
Download:TweetDeck Download.
Developer URL: Iains posterous.
Twitch
Download:Twitch Download.
Developer URL: Richard Fisher.
Universal Inbox
Download:Universal Inbox Download.
Developer URL: Webauthor.com.
twhirl
Download:
twhirl Download.
Developer URL: twhirl.org
Posty
Download:Posty Download.
Developer URL: Spread Funkyness.
Tweetr 3.4
Download:Tweetr 3.4 Download.
Developer URL: Tweet-r.com.
SedThink Twitter Client
Download:Sedthink Download.
Developer URL: Sedthink.com.
Description: TwitterFox is a Firefox extension that notifies you of your friends’ tweets of Twitter. (previously known as TwitterNotifier).
Description: Twitzer is a Firefox extension which lets you post text longer than 140 characters on Twitter.com. It can also convert TinyURL.com links to actual links so that you are sure what link will open.
Description: TwitterBar is an extension for the Mozilla Firefox Web browser (originally written by Tony Farndon) that allows you to post to Twitter from the Firefox address bar. Just type your tweet in the address bar and click the TwitterBar icon to send it to Twitter. You can also post the URL of the page you’re currently reading by clicking the TwitterBar icon with typing in the address bar.
Description: TwitBin is an extension for firefox that brings the power of twitter right in your browser. You can quickly and easily send and receive messages via twitter in your firefox browser. Nice and simple.
Description: TwitKit is a Twitter sidebar for Firefox. TwitKit has a 6-section interface, using tabs to separate content. You can view the Twitter public timeline, your user timeline, a list of your friends and their latest tweets, a list of your followers and their latest tweets, @replies made to you, and stats about your account.
Description: DashBlog is a FireFox extension that lets you grab videos on any webpage and quickly post them to your blog.
Description: TwittyTunes is a FoxyTunes companion Firefox extension – it allows you to post your currently playing songs to Twitter with a click. As a bonus, you can also post the websites you’re visiting, videos you’re watching and more!
Description: Socialize your browser. Bring all your friends in your browser with Yoono and: – Follow what they are doing – Chat with them wherever they are – Discover and share any content by a single drag & drop Support: MSN, Yahoo, Gtalk, AIM, Facebook, MySpace, iMeem, Flickr, Twitter, Friendfeed… Yoono also synchronizes your bookmarks between your different computers See long description for all additional Yoono’s features
Description : FutureTweets.com is a free service that lets you schedule your Twitter messages. Send it at a specific time in the future or send a reoccuring Tweet daily, weekly, monthly or yearly!
Description : Qwitter allows you to find out who has quit following you, and at what message they stopped. This service is definetly for twitter-addicts (I checked).
Description : Just Tweet is a directory for Twitter users, it makes it easier to follow people with similar interests to your own.
Description : Typetweets is an up to the minute look at the typographic discussions happening across Twitter, and a great way to discover interesting type-themed bits on the web. 
Description : This site gives real time Twitter User stats and analytics. Really interesting viewing.
Description : With this service you can create an event and allow your users to RSVP back to you.
Description : A simple but usefulidea from Twitly, basically you can seperate everyone you follow on Twitter into groups.
Description : Your Twitter Ratio is the ratio of your followers to friends (or people who you follow). It is measured with the TFF Ratio (Twitter Follower-Friend Ratio). The higher the ratio, the more Twitter heat you pack.
Description : Tweetlists shows you the most popular tweets in the last 24 hours.
Description : SecretTweet was created to allow Twitter users to share secrets anonymously.
Description : @answerme is a little tool to help you track questions you ask on Twitter. Imagine Yahoo! Answers lite built on Twitter and you've got a good idea of what it is doing.
Description : Add a daily updating TwitterCounter to your blog so everybody can see how popular you are. First Check your Twitter Account by entering your username in the search box, then get the button code, and copy and paste the code on to your blog.
Description : TwitPic lets you share photos on Twitter, you can post pictures to TwitPic from your phone, or through the site itself.
Description : View a live via Google Earth of live tweets as they happen.
Description : Enter up to 5 keywords into the boxes and see how often they appear on Twitter. I am not really sure what you could use this tool for (other than marketing), but it did keep me amused for a good 15 minutes. Try it.
Description : Foamee tracks who you owe beer or coffee to (and vice versa) via Twitter.
Description : The simplest of simple. It asks the question: Is twitter down for just me or everyone? I have bookmarked it, you never know.
Description : Tweetake allows you to back-up your followers, people you are following and Tweets with just one click.
Description : Advertisers create campaigns providing a message and some keywords, it finds matching twitterers are selected, costs are calculated based on # of followers and hotness of the topic.
Description : Twiggit is an automated service that lets your friends on twitter know what articles you digg.
Description : You Use LazyTweet via Twitter and leave a question or request of some sort and wait for some feedback. 
Description : Twitag is a tag finder for twitter, the goal is to facilitate and organize the most recent content tagged by users.
Description : You can track your biorythm easily via 
Description : If a link is posted within a tweet,it is collected and numbered. For tweets with tinyurls we also reverse the URL so that you can see in your browser where the tweet realy is linking.
Description : EmailTwitter.com allows you to post Twitter updates and retrieve your Twitter timeline via your cellular phone or other e-mail enabled mobile device, without incurring SMS fees.
Description : When you give your Twitter credentials you are supplied with a TwitterMail email address. For instance abcdef1234@twittermail.com. If you send an email to that address it will be posted to Twitter.com.
