If you book accommodation for over $50 on Booking.com, you will receive $25 off on your next Booking.com booking. This $25 is applied on your second Booking.com booking after the current one.
Official booking link: Click here!
My Review
Not really a great deal. If it were an instant $25 discount, it would be nearly a 50% savings when used well. But because it only applies on a later second booking, it mainly helps people who have an immediate need to book again.