From Brana Bujenovic:
Rot-13 Addin is Rot-13 encoder/decoder for Microsoft Outlook 2000/2/3. If you want to encode/decode text using rot-13, just replace each English letter with the one positioned 13 places forward/backward along the alphabet. The goal of such a simple encryption is to hide part of your message temporarily, and force recipient(s) to read the rest of the text first. Version 184.108.40.206 has Hold down Shift key (while pressing (Un)Scramble - Rot13 menu item) to insert spoiler delimiters. Removed some obsolete functions. Fixed a crash that would occur when the add-in is disabled and then re-enabled during the same session.