No. We do not have a minimum sign up requirement and there is no long-term contract. Your service is month-to-month. You can sign up for one month, use the service, and then cancel 4 days prior to your monthly billing date and you will only be charged for your one month of use.
There are two considerations that are important to note.
If you cancel and then choose to re-join within 60 days, all of your address book contacts, favorite eCards and custom settings will be remembered and available.