I know you can add new styles to paper clip and then use process! method to force paperclip to fill in the missing styles. But what if you want to ditch the old styles that you are not using any more. 

For example I have styles iphone and ipad, and I changed my mind and would instead like :large and :medium with slightly different dimensions instead of :iphone and :ipad. 

In particular I'm hosting my images on s3 since my app is on heroku. I would like to remove all the folders on s3 pertaining to :iphone and :ipad styles. Is there a rake task for removing select styles?