As far as Im aware, there is no default support for this. You'd need to implement your own system for updating text in the textbox that would immitate scrolling text.
However, I'd have a look at the demo applications that are installed with the controls and use either a rad rotator or even a rad progress bar (where you can use your own image)
Hope that helps
Richard
There is no telerik control that does this, but i have prepared a CustomRadTextBoxControl that will do this, please see the following example, it should help you accomplish your task: