Emacs function to insert a random UUID on-demand.From http://ergoemacs.org/emacs/elisp_generate_uuid.html

new_gist_file.el

(random t)

(defun insert-random-uuid ()
  "Insert a random UUID.
Example of a UUID: 1df63142-a513-c850-31a3-535fc3520c3d

WARNING: this is a simple implementation. The chance of generating the same UUID is much higher than a robust algorithm.."
  (interactive)
  (insert
   (format "%04x%04x-%04x-%04x-%04x-%06x%06x"
           (random (expt 16 4))
           (random (expt 16 4))
           (random (expt 16 4))
           (random (expt 16 4))
           (random (expt 16 4))
           (random (expt 16 6))
           (random (expt 16 6)) ) ) )