The cards in the Hyper House stack provide the structure of the BBS: what order the user must do things in, and what parts of the BBS he can get to from other parts of the BBS.
Cards are included for general notices, logging in, handling new users, and an overall menu. These cards can be duplicated or added to to change or augment the structure of the BBS.
Services can also be made available before login, the login process can be removed entirely or reduced to just a matter of getting the user's name, and there can be multiple login points to limit access to different portions of the system.