How to say goodbye

Maybe it's a sign of the times, but here's a great article on how to write a final farewell email to your co-workers. The author points out that there is no standard etiquette like you might find for general email. What are some of the author's suggestions?
- err on the side of less information rather than more
- limit the melodrama
- be gracious to your supporters
- use humor sparingly
Actually, those are pretty good rules for most email.