Chromed bird twitter extension for Google Chrome is by far the best I have seen. It may lack on things like on tweet video and picture viewing capabilities, but it is incredibly light weight and have all the basic functionalities one would ever want.
- Down to earth light weight.
- All normal twitter functionalities including retweets, old school retweets, reply and so on.
- Supporting lists and favorites timelines.
- Follow your timelines and navigate through your tweets.
- Create short URLs within the extension.