TweetDeck - TweetDeck is your personal browser for staying in touch with what’s happening now.
Choqok - Choqok - KDE Micro-Blogging Client The name comes from an ancient Persian word, means Sparrow!
Tweetbot - Sync your timeline across your iPhone, iPad, and Mac. Mute tweets by user, hashtag, tweet source, or keywords (including regex). 3rd Party support for image, video, read later, and timeline sync services.
Earthquake - Terminal-based Twitter Client with Streaming API support. Only supports Ruby 1.9 and later.
YoruFukurou - YoruFukurou (NightOwl) is a Twitter client for Mac OS X, designed for Twitter addicts.
Echofon for Twitter - Download Echofon apk 3.1.3.3 for Android. Echofon for Android - A super clean Twitter app