[Orgmode] change color of headline depending on TODO state ?

[Eliseo Papa]

Hi all,

I was wondering if somewhere in the seemingly-infinite org  
flexibility, there exist a way to color the headlines depending on the  
TODO keyword.
That is, change not only the color of the keywords, but also of the  
associated headline. It would make it easier for me to scan through  
the document looking for (say) waiting tasks without having to set  
tags, or custom agenda views.

Many thanks,
eli