When testing different user roles in Drupal, there is a handy trick that leverages Gmail's ability to pass information in via your email address. For example, if your Gmail email address is "email@example.com" you can pass additional information by adding a plus sign before the "@" and the additional information after the plus sign. For example, "firstname.lastname@example.org". When creating test users with different roles, the role can be specified in the email address using this technique. This allows you to create the roles without having to register new email accounts and allows you to see what email a role's user receives.