I have been using drop.io for a while as a good way of storing files and allowing students to access files that they needed for class work. However, drop.io has now been brought out by Facebook, and their service is coming to an end. I am trying to investigate some possible alternatives.

www.dropbox.com is a popular site that allows you to have 2GB free storage and access your files over many devices, and publicly share links to specific documents. I have tried this, but the size of the free account is restrictive. However they have lots of good integration through apps etc.

www.adrive.com this gives 50GB of storage, but does not have the ease of syncing that dropbox allows, or the integration tools.

Google Docs! It is coming down to GDocs for me. I can upload any document i want and then give the students the url to share the file if i need to, and even allow them to work collaboratively with me.