• Add to Any (plugin) – Help readers share, save, bookmark, and email your posts and pages using any service, such as Facebook, Twitter, Digg, Delicious, and over 100 more social bookmarking and sharing sites. The button comes with Add to Any’s customizable Smart Menu, which places the services visitors use at the top of the menu, based on each visitor’s browsing history.
• TweetMe (plugin) – Automatically shrinks and sends your url to twitter and lets your users share your content on twitter. There is also a non-wordpress version located here
• TwitPress – Submits a user definable tweet to your twitter account notifying any twitter followers or friends that a new blog entry has been published on your blog (or an existing published entry has been edited). Supports inclusion of a permalink to your blog posting in the tweet.
• TwitterCounter – Allows you to integrate TwitterCounter badges on your blog.
• TwitThis – TwitThis is an easy way for people to send Twitter messages about your blog post or website.
• MyTwitter – MyTwitter allows users to display their recent Twitter status updates (tweets) on their WordPress site and update their status through the Options page. Includes customization options including number of recent twitters to display, formatting options, and stylesheets. It can be called as a function or used as a widget.

I copy-pasted some of the descriptions from their original websites, I hope you don’t mind :)

Try’em out, enjoy them, and don’t forget to comment on this post.

Cheers!