Just came across when I was browsing for WTC Observatory NYC tickets. They had a link on their website that asks you to enter your email id and you will get a mystery e-gift card code which can be used at Century 21 stores. The value of the e-gift card can only be verified at checkout.
Below is the link:
Gift cards usually come within 5-10 minutes to your email. This E-gift Card is good toward the purchase of merchandise online at C21stores.com or in any Century 21 Department Store. This mystery E-gift card expires on 12/31/2016.
You can locate your nearest store here:
I found this a very good deal..it's like atleast free $5 if not $500..