Open shell in directory corresponding to buffer

shell-here.el

(defun shell-here ()
  "Create new shell rooted at default-directory and open it in
   new window if there is no other shells associated with
   default-directory, open existing shell otherwise."
  (interactive)

  (let* ((buffer-dir (directory-file-name (expand-file-name default-directory)))
         (shell-buffer-name (concat "*shell*<" buffer-dir "/>")))
    (shell shell-buffer-name)))