lgrep.el

(defun raellear-lgrep (regexp &optional files confirm)
  (interactive
   (progn
     (grep-compute-defaults)
     (cond
      ((and grep-command (equal current-prefix-arg '(16)))
       (list (read-from-minibuffer "Run: " grep-command
				   nil nil 'grep-history)))
      ((not grep-template)
       (error "grep.el: No `grep-template' available"))
      (t (let* ((regexp (grep-read-regexp))
		(files (grep-read-files regexp))
		(confirm (equal current-prefix-arg '(4))))
	   (list regexp files dir confirm))))))
  (lgrep regexp files "/insert/your/directory/here/" confirm))

(global-set-key (kbd "C-c g") 'raellear-lgrep)