Sometimes the simplest ideas are the best. Not implying that Twitter Grid was simple to develop, as the development team must have worked hard to provide accessible / easy to use options.
Here are some of the benefits:
1. Multiple grid patterns available
2. Great for multi-tweets, for example both corporate and indvidual, linked to a common owner
3. Monitoring activity with colleagues
4. Assistance in understanding valuable contributors Vs imposters!
5. Instant access to replies.
Here is the link to this very useful application: http://tweetgrid.com/
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