kill-buffer-file-name-or-name.el

;; Car salesman, *slapping roof of defun*: this bad boy can fit so much damn file management convenience in it.

(defun kill-buffer-file-name-or-name ()
  "Pushes a useful path to the kill ring.

When visiting a file, pushes the file's path. In dired,
pushes the path of the file at point or else the current
directory. In magit, pushes the path of the file at point or else
the repo's root. Otherwise, pushes buffer's name. Displays
whatever was pushed in the message area."
  (interactive)
  (let ((buffer-name 
         (escape-spaces
          (cond 
           ((equal major-mode 'dired-mode)
            (condition-case nil
                (dired-get-filename)
              (error
               (dired-current-directory))))
           ((equal major-mode 'magit-status-mode)
            (concat
             (magit-get-top-dir)
             (nth 1 (magit-section-path (magit-current-section)))))
           ((buffer-file-name)
            (buffer-file-name))
           (t
            (buffer-name))))))
    (kill-new buffer-name)
    (message buffer-name)))