This app was removed from the App Store.
Mac OS Social Networking
Kiwi is the customizable Twitter client for Mac OS X. It has tabbed windows for multi-account viewing, rules for filtering, and 9 great themes to suit any style.
Kiwi comes with 9 great themes: some simple and some wild. Plus you can download more at http://kiwithemes.com , and even make your own!
Kiwi's tabbed window let you choose one merged timeline, or a whole screen full of accounts and searches. No matter how you like to use Twitter, Kiwi can work with you.
Kiwi has great power-user features: filter rules to screen out unwanted tweets, account groups to keep things organized, and saved searches to keep tabs on what's important to you.