I tried following the directions on the web site - http://www.boost.org/users/download/

Which states the following:

 

Accessing the Boost Subversion Repository

The Subversion repository can be accessed in several ways:

• Anonymous, read-only access to the Boost Subversion repository is available at http://svn.boost.org/svn/boost. To access the current Boost development code, for instance, one would check out from http://svn.boost.org/svn/boost/trunk. For example, using the command-line svn, one might use:

  svn co http://svn.boost.org/svn/boost/trunk boost-trunk
  On Windows, TortoiseSVN provides an
                  easy-to-use, graphical interface to Subversion.

However it didn't work.  It started to, it got part way through the download then asked for a password.  Now that's all it does:

~/boost $ svn co http://svn.boost.org/svn/boost/trunk boost-trunk
Authentication realm: <http://svn.boost.org:80> Boost SVN repository Subversion Access
Password for 'user':

svn: OPTIONS of 'http://svn.boost.org/svn/boost/trunk': authorization failed: Could not authenticate to server: rejected Basic challenge (http://svn.boost.org)

What password is expected, and why is it not listed on the web page in the download instructions? 

http://www.boost.org/users/download/