Make BuildWorld options

[tomt at callcds.com]

I was reading this
http://lists.freebsd.org/pipermail/freebsd-small/2003-December/000125.html

And noticed that it talks about a make.conf for use with buildworld with
options like
NO_CVS=         true    # do not build CVS
NO_CXX=         true    # do not build C++ and friends
NO_BIND=        true    # do not build BIND
NO_FORTRAN=     true    # do not build g77 and related libraries
NO_GDB=         true    # do not build GDB

Is there a list of these options anywhere that explains what each option
does?

I am trying to build a very minimal system using buildworld and everytime
I try of these options I have to way the hour or so that buildworld takes
to see if the option changed anything.  I am trying to bring the size of
the build down currently it is 172 mb.  I would like to get it to 50mb or
so.

This system is for an embedded router, I am only using racoon, ipsec,
ipfw, ssh, 2x ethernet cards on an freesbie type boot cd.

Thanks
Tom