TweetSuite –  A Twitter-WordPress integration plugin that includes server-side TweetBacks, ReTweet-This buttons, digg-like Tweet-This Button, automatic tweeting of new posts and some widgets.

Twitter Feed – Posts your blog updates to your twitter account. Login to twitterfeed using your OpenID, provide the URL for your blog RSS feed, and how often to post to Twitter.

TweetMeme button – Aasily allows your blog posts to be retweeted.

Twitter Tools – This wordpress plugin creates an integration between your WordPress blog and your Twitter account. Pull your tweets into your blog and create new tweets on blog posts and from within WordPress.

DiggDigg- An awesome tool that displays social buttons on your website/blog.

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