The Insidious Big Brother Database (BBDB) is a contact management
utility created by Jamie Zawinski for use with Emacs. It is tightly
integrated with several mail and news readers, allowing it to create
database entries directly from mail and news messages. As is usual
with applications for Emacs, this record creation can be configured in
many ways, ranging from a boolean create/don't create setting to
creation based on the result of a user-supplied function.
Database records can be used to store many types of information, from
name and address to URLs and X-Face images. This information can be
displayed when a message from an entity named in a database record is
received. In addition, messages from database members can be tagged in
the Gnus Summary Buffer, and Gnus scoring can be configured based on
the contents of database records. Supercite citations can even be
preset through the use of records in the BBDB.