Recently Posterous joined Twitpic for sharing images on Twitter. Posterous is a simple place to post anything including images, videos, mp3 and files by sending an email to post@posterous.com in reply you can see your post at http://yourname.posterous.com.Posterous new API let users to post your image to some of the most popular Twitter clients either from desktop or from your iPhone.
Twitter users of TweetDeck, check this out. Facebook Connect and Seesmic Desktop is a dream application for the frequent status updater, group lover, and social media meme tracker. Has multiple columns that can be rearranged via drag and drop, customizable groups, Twitpic functions, etc.
I started using Seesmic Desktop a few days ago and have found it to be much better than TweetDeck. One of the key features for me is that it allows you to manage multiple Twitter accounts.