Download: [Removed] See Lutz Roeder's site for the new additions.
As the title suggests the control in the provided download is based on Lutz’s Roeder’s Command Bar control (http://www.aisto.com/Roeder/dotnet/ ). One of the main new features I added to the library was the DropDown and SplitButtons.
Split Button à 
Dropdown Button à
Additionally, there was no setting aka .NET property for displaying the Text of the button. The Buttons now support displaying an image, text or both. Along with these new capabilities is the Image and Text relation property. The buttons are now capable of displaying the text to the right of the image as it’s used in Internet Explorer, or underneath as is the case with Outlook Express.
IE
Outlook Express
According to the MSDN documentation (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/commctls/rebar/rebar.asp ), the Rebar control is a container controls for any control or window as it is known in the Win32 world. The most popular implementation is of course Internet Explorer aka Windows Explorer.
I took the liberty of creating a … well see for yourself…
Keep in mind I only added very limited functionality for the demo.
Microsoft has however supplied some information regarding implementing an Explorer like app. See http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/commctls/faq/ietoolbar.asp for further details.
A couple of important notes:
I have modified the object model from the original found on Lutz’s site. Unfortunately, I don’t recall all the changes. Also, when working with the bits, just know that the code in initialization phase of the control is critical. This is a function of how the Win32 (Windows Common Controls) work. I have added things like “//new Code here” to demarcate changes form the original where possible, but not everywhere. Also, much of the new functionality I added uses Windows Constants defined by the MSDN documentation http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/commctls/toolbar/toolbar.asp . The Windows SDK will be needed (this is an option when installing Visual Studio), to define further constants that I did not provide.
One last thing to consider, because there is extensive use of PInvoke throughout, remember to clean up unmanaged resources.
Enjoy!