I was not familiar with this concept. It's a nice way to create your own search engine from sites you are comfortable with. I played around and created two search rolls...book review sources and my favorite gaming sites. I'm addicted to playing hidden object games except I'm cheap and only play the free one hour trial. So it's nice to be able to easily search the sites I trust for downloads.
Check out my search rolls!
I could see this being useful at work on several levels. At MR we frequently use IE's favorites for potentially useful sites. Now we could create a search roll for a some of our similar sites and only have one link. For example, we could put all our car sites on a roll, social services on a roll and so on. That would save so much space and let staff search all related sites at one time. Very helpful!