Building some parts of CVS

[AGC <agcarver+netbsd%acarver.net@localhost>]

When building the new system from the CVS updates, is it possible to 
select only portions (e.g. base, comp, some of X) instead of everything? 
 As an example I want to be able to skip games and most of X (I don't 
need a desktop) but I'm not sure how this works compared to the CD based 
install with the tgz's.