SHELL stations offer a Platinum Mastercard that gives you 5% credit on SHELL gas purchases.

Currently saves 21c+ a gallon.. Most shell stations are between 4.15 and 4.30 today.

The net price is cheaper than paying cash at ARCO.

Applications are available above almost every SHELL pump.

http://www.shell.us/home/content/usa/products_services/shell_cards/mastercard/mastercard_calculator.html