Edit file in file storage

How about being able to directly edit files kept in File Storage?

Everytime I want to change anything from a file, I have to download it, edit and erase the copy from the file storage; THEN I can upload.

I use public computers and I don't like leaving my stuff around, so after that I also have to erase the copy that's left in the computer.

It would be much faster, confortable and probably secure to be able to change the document that's already uploaded, and not copies of it.