When you subscribe to ResearchTies and tell others about it, you can obtain an extension to your current expiration date. If someone you refer to the program decides to subscribe, ask them to send the email address of your account in an email to firstname.lastname@example.org to inform us that you are the person who referred them. Your expiration date will be extended by three months. Refer more than one person, and you will continue to extend your account.
Talk to your friends and spread the word!