An alternative to multiplying versions of a document and filing those versions is using Google Docs.
I find this tool very appropriate to send feedback to students, because it allows people to have a conversation over a document.
Adding comments that are displayed with the date and time is an interesting feature that can serve well in collaboration projects. If a written assignment has to be checked and edited by another student, it is easy for the teacher to follow the chronology of the edition process.
The best part of all is that storage devices are not required anymore, as all the work is saved in a virtual drive.
