In 2010, I wrote a utility for Antair that allowed us to easily view the email headers of any email in the BlackBerry inbox.
The application integrated nicely with the BlackBerry inbox, making it really simple to view the headers of any incoming email message.
We released the application as a free app shortly thereafter. From what I heard, quite a few system administrators have found a use for it.
Today, I cleaned up the code a bit, and released the project as open source.