man-db is an implementation of the standard Unix documentation
system accessed using the man command. It uses a Berkeley DB
database in place of the traditional flat-text whatis databases.
man-db is used by several popular GNU/Linux distributions,
including Debian,
Ubuntu, and
SuSE. It also compiles and runs on a
number of proprietary Unix systems.
The Savannah project for man-db will, I hope, be regularly updated with new releases. Revision control is handled by bzr; the main development branch can be checked out from http://www.chiark.greenend.org.uk/~cjwatson/bzr/man-db/trunk/.