Prefix for EVERY newline

[DrMemory]

I know how to set-fill-prefix; but what I would like is for a prefix
to be prepended to _every_ newline which I start. Actually, I would like
to add a hook to read the first n characters off of the preceding line
and use them as the first n characters of the succeeding line. Can
this be done? 

Thanks in advance.
--
Scott Swanson

"My operating system? Emacs. Linux is just the fileserver....."