I also use:

  (defun go-up-one ()
    (interactive "*")
    (scroll-down 1))
  (defun go-down-one ()
    (interactive "*")
    (scroll-up 1))
  (global-set-key [S-up] 'go-up-one)
  (global-set-key [S-down] 'go-down-one)

so shift-up and shift-down scroll by one line no matter where the cursor is; and the cursor can often remain where it is, until you scroll too far. (Maybe it's outdated, since I did it a long time ago.)