One rare case, but rather necessary due to the requirement to be able to display the Creole spec in Creole, is to be able to display a closing triple curly brace within a nowiki block. There are currently two proposals:
Space #
This requires that a nowiki block have no leading spaces to start and no leading spaces to end. So, the triple curly braces must start the line. Therefore, if you want to display triple curly braces within a nowiki block, you would put a space in front of them, since only triple curly braces at the beginning of a line end a nowiki block. This solution also makes it impossible to display closing triple curly braces inline.
Tilde #
Another method is to display the triple curly braces if a tilde is put in front of them like }}}. This is the way JSPWiki works and therefore is Not New.
Please feel free to improve the explanations of the above methods and vote on which you prefer on Creole 1.0 Poll.