** show all
   CLOCK: [2009-09-15 Tue 07:51]--[2009-09-15 Tue 08:51] =>  1:00
   :PROPERTIES:
   :exports:  both
   :DATE:     2009-11-20
   :END:

#+begin_src ditaa :file blue.png
   +----------------------+
   |                      |
   |                      |
   |          +-----------+
   |          |           |
   |          |           |
   |          |           |
   |          +-----------+
   |                      |
   +----------------------+
#+end_src