I think you are mentioning about 'ticker' control.
Well, you can achieve this using the javascript marquee and but of ajax. Here are the steps
1. Place a horizontal marque in the place where you want the ticker.
2. Get the handle of the marquee from javascript.
3. Write a script service for Ajax to retrieve the ticker content.
4.Use javascript setTimeOut function to pool this method on desired interval
5. Upon webservice call complete, update the marquee.
Thats it!
Thanks,
Atanu