In dired, M-> and M- never take me where I want to go.

(defun dired-back-to-top ()
  (interactive)
  (beginning-of-buffer)
  (dired-next-line 4))

(define-key dired-mode-map
  (vector 'remap 'beginning-of-buffer) 'dired-back-to-top)

(defun dired-jump-to-bottom ()
  (interactive)
  (end-of-buffer)
  (dired-next-line -1))

(define-key dired-mode-map
  (vector 'remap 'end-of-buffer) 'dired-jump-to-bottom)

That is, now they do.

Instead of taking me to the very beginning or very end, they now take me to the first or last file.