Below is the error message shown after a session timeout for Bank of America Privacy Assist:

This error attention caught my attention as it had an extra piece of information (somewhat?) unrelated to what I was doing at the time. Typically, the error message pattern is: (1) what went wrong? (2) why it happened, and (3) what should be the user next steps. What I notice above is an additional ingredient that can be called: “something for fun”. Now, the message above may be static, i.e. the user is always shown that piece of informational text warning about identity theft. But the treatment above does inspire the thought of having an extra part to error messages that is dynamic and gives something “random” and useful to the user.

For example, I’m thinking as a pattern for a fatal error page, have something like:
1. Something went wrong
2. Here is the fun fact of the day