TweetThisText

TweetThisText – Tweet chunks of text. Highlight what you want to tweet and use the bookmarklet to create a link to your quote. Also allows users to view the original source.

TweetPo.st

TweetPo.st – update your Facebook selectively.

act.ly

act.ly – Sign in to Twitter (OAuth, yay!) and petition @user to do something. Nice stats on who has signed up and petitionee (this is actually a word) responses.

twitcam

twitcam – connects up with your webcam so you can stream live to Twitter. NB: Requires you to login in with your Twitter username and password. I haven’t tried this.

Twitteron

Twitteron – Adobe AIR Twitter client (Windows, Mac, Linux). Features include changeable skins. Ooh.

TwitChuck

TwitChuck – Greasemonkey script for reporting spammers from their profile page on Twitter.com or from search results on Search Twitter.

PicFog

PicFog – real time image search.

TrueTwit

TrueTwit – validate your followers. You sign up and any new followers have to complete a CAPTCHA. Not tried this myself. If you have, please leave a comment.

tweeps.info

tweeps.info – twitter user stats, “What do they tweet about? How much do they tweet? How social are they? Do they use hashtags? Share URLs?”

twittergrid

twittergrid – see who is following who. Enter a username to display the avartars of that person’s followers, hover over to see biog. info and latest tweet. Pretty, but I tried it for @infobunny (that’s me) and it only showed some followers, not all.

Overlapr

Overlapr - enter 2 Twitter usernames to find out what they have in common in terms of friends and followers.

find2follow

find2follow – suggests Twitterers for you to follow.

TwitPrint

TwitPrint - print your tweets. Not sure why and I’ve not tried this. It requires your username and password btw. If you’ve used this please leave some feedback.

TwitVid

TwitVid – share videos on Twitter.

Tweetrans

Tweetrans – translate your tweets.

PingWire

PingWire – almost live feed of images posted to Twitpic.

Flickr my background

Flickr my background – syncs your Twitter background with your latest Flickr uploads.

img.ly

img.ly – another way to share photos on Twitter

Twinbox

Twinbox – plugin for MS Outlook.

TidyTweet

TidyTweet – filter your Twitter stream. Allows for:

• Automatic or Manual Approval of Tweets
• Custom Bad Word Filtering
• Whitelist or Blacklist Twitter Users
• Auto-rejection of Tweets from New Accounts
• Auto-rejection of Tweets with Multiple Trending Topics

Some of this seems a little sad, like “auto-rejection of tweets from new accounts” :( Currently free, but they say they are looking into pricing models.