The public folder in Dropbox allows users to link to your file. I know you can do similar things with Google’s services. This is easier for me to use than Screencast to share that the school want me to share with all students. Drag the attachment from the email to the Dropbox folder. Ask for the sharing link. Tweet an announcement with the link. I can also click on the link from my course announcement page to project the hand out if its an announcement that deserves class time as well.