Rails File Management and Email Distribution combined

I'm looking to have a file manager on my rails app - similar to dropbox (I was going to follow this tutorial: http://ift.tt/1m1wurD) but I am also trying to allow users to share the file via emailing it out to a contact list of emails saved in the app. I currently have a contact list in my members controller with :email as one of my fields. I am unsure where how to go about this. Are there any gems anyone would recommend?