Nambu

Nambu may be the most powerful Mac Twitter client out there. But it can boil itself down to a simple window if that is all you want. In fact, you get three different ways to view your information: a simple window, a window with a sidebar (pictured) and a multi-columned window.
There are all sorts of extra features in Nambu, such as the ability to group your friends and only view tweets from a group. You can also list all of your friends or followers inside the interface. You can open up a friend’s info in a separate window and view their recent tweets there. You can even dig down and see who they are following and who is following them. Things like the current trends are easily accessible, as well as searching.
Nambu is a free native Mac application, not requiring Adobe AIR or anything else. It also promises future support for Twitter-related services like FriendFeed and Ping.fm.
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