Separate Website From Application with VirtualHosts

Question

I would like to host 1 part of my project on the www.domain.com and domain.com, but if it's not either of those, route it to another separate site on the same box.

This should explain what I am trying to do, but no clue how to go about it:

<VirtualHost *>
        <Directory /var/www/domain>
          Options FollowSymLinks
          AllowOverride None
          Order allow,deny
          Allow from All
        </Directory>

        ServerName domain.com
        ServerAlias www.domain.com

        DocumentRoot /var/www/domain
</VirtualHost>

<VirtualHost *>
        <Directory /var/www/non_domain>
          Options FollowSymLinks
          AllowOverride None
          Order allow,deny
          Allow from All
        </Directory>

        ServerName *.domain.com

        DocumentRoot /var/www/non_domain
</VirtualHost>