Some defuns to insert pairs of useful programming delimeters.

insert-pairs.el

(define-key global-map (kbd "C-M-j")
  (defun insert-surrounding-parentheses (&optional arg)
    (interactive "p")
    (dotimes (i arg) (insert "()")
	     (backward-char 1))))

(define-key global-map (kbd "C-M-k")
  (defun insert-surrounding-braces (&optional arg)
    (interactive "p")
    (dotimes (i arg) (insert "{}")
	     (backward-char 1))))

(define-key global-map (kbd "C-M-l")
  (defun insert-surrounding-brackets (&optional arg)
    (interactive "p")
    (dotimes (i arg) (insert "[]")
	     (backward-char 1))))