Every browser offers "right click -> save as" functionality, its simply not possible to prevent a user from saving the shared content. Once its there in the browser on the users screen, its outside of any control Dropbox can enforce.
Ive used this analogy many times before, and its still as apt as ever - the software, film and music industries have collectively spent billions of dollars trying to restrict users from doing what they want with content, and they have collectively failed because I can today go to a particular website and get any piece of software, any film and any song for free. Dropbox isnt playing that game.
That's not possible. If something can be viewed on the Internet, then it can be downloaded (and in most cases, has to be downloaded to the browser cache to be viewed).
Sometimes, we like some to view our files WITHOUT being able to DL them. Is there a chance that Dropbox will ever include this feature ??? would be helpful to many of us I'm sure. Thanks!