I let a RapidSSL cert lapse lately. They sent me 11 emails about it. They were really rather insistent:

    Early bird special: Renew your <website> to save
    Keep <website> Secure, renew your SSL
    Last chance to save: Your <website> is expiring
    ACTION REQUIRED: Your SSL needs attention
    FINAL NOTICE: Your SSL expires tomorrow
    LAST CHANCE: Your SSL expires today
    SECURITY ALERT: Your <website> may not be secure
    ACTION REQUIRED: Your SSL needs attention
    SSL EXPIRED: Renew to rescue
    CALL US: SSL for <website> is expired
    Your last SSL expiration notice for <website>

I was actually relieved when they finally stopped mailing me...