For today only, you can get $20 off a $100 or more purchase at Aeropostle. The offer is only available online and is good for today only. You can head over here to check it out. Use coupon code: TODAY20 at checkout. They are also offering Free shipping on orders of $100 or more.
There is also a $10 off $50 coupon which you can use in store through 12/24.
(thanks Jackie!)