Twhirl is a desktop client built for Twitter and a few other services -- identi.ca, laconi.ca, Friendfeed and Seesmic Video. Because Twhirl emphasizes compactness, it doesn't use the multi-column format of programs like HootSuite or TweetDeck. However, in the long run, it's almost as easy to manage. Twhirl has been acquired by the same folks who created Seesmic, but development continues on Twhirl as a separate product. Twhirl's design works best for people with a low volume of messages in their Twitter streams or casual users who want the flexibility of a desktop client without the bulk.
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