We may find that the standard select options on our forms cannot satisfactorily handle all situations. For instance, on our example Speaker Registration form we have an honorific title select list which covers all the basics (Mr, Mrs, Ms, and so on.). This list does not adequately provide for persons who require additional options, such as those in the military who need to be addressed by their rank, for example Sgt, Lt, or Capt.
The Select (or other) module enables our form users to enter their required title when it does not appear on our list of options.
Let's proceed to the project home page to download, install, and enable the module: http://drupal.org/project/select_or_other.