my customer asked for the possibility to present "documents" (that is Excel sheets, Word docs, PDFs, pictures, videos...no, he didn't get more specific) via web browser to a user while prohibiting saving the content. My first reaction was a clear "no" (I think I remember a discussion over year a year or two ago): if I present a file the user can always save it, either by the browser's download dialog or by the native application that shows the content (download dialog in Excel). Now I wonder, may be there is a (commercial) software out there which offers somekind of a web-based viewer for several file types? This viewer component (Javaapplet based...?) is responsible for displaying the data...? Anything like that?
I saw some stuff in my Servlet studies that I intend to get back to that suggests an ability to present data in the needed manner. Once you put it in the browser window there is little to prevent the savy from retaining a copy for perusal.
Reliable prevention will be a matter for proprietary tools specific to a browser.
"The differential equations that describe dynamic interactions of power generators are similar to that of the gravitational interplay among celestial bodies, which is chaotic in nature."