Tim Hortons Rim Roller

I saw one of the most unique ideas I have seen in a long time today at the local Zellers store, they are selling a key chain that has a tool attached to cut and roll your coffee cup rim. What an idea, when you are done with your coffee you slide this down over the rim and it cuts it and when you pull it back up it un-rolls your rim. It's only 2.49 and has to be a cool idea for sure.