In fact, if Buzzbird is missing a feature that you want, and you know Javascript and/or CSS and/or XML, then you can even feel free to add it yourself!
Features:
- Multiple Account Support
- Desktop notifications
- Service filtering
- Conversation views
- Selective filter views (can choose Timeline, @mentions, direct mentions)
- Retweet, Reply, Unfollow, and Favorite button on each Tweet
- Built-in URL Shortening (currently via is.gd)
- Menu to insert emoji in tweets
- Read/Unread count in status bar
- Click on a users avatar to see more information about them, or to follow/unfollow them.