You can receive a code for a 15% discount off of Southwest Airlines fares by going to this site and entering your Visa Signature card number.

If you check your Visa card and it says “Visa Signature” on it, you are eligible. Once you enter in your sixteen digit card number, they will email you the discount code.

Purchase must be made between January 20 and April 30, 2011 for travel before June 1, 2011.