One of, if not the most, popular Twitter clients on the Mac is Twitter for Mac (formerly known as Tweetie). But along the way it has had some aesthetic changes that a lot of people have mixed feelings about, especially the 3D icon that the app uses. A lot of people like the old 2D style icon or the iOS version of it and use another program like CandyBar to do it. But did you know that Twitter comes with the old 2D icons built in? I found that out by accident, so I made this video showing you how to do it.
You can find Twitter for Mac in the Mac App Store.