Kroger offering $ .40 off on gasoline fill up WYB $100 in gift cards

Kroger is offering $ .40 off per gallon on a fill up when you purchase $100 in gift cards now through December 11, 2010.  If you have a 20 gallon tank that is about an $8.00 savings. I was thinking about purchasing Kroger gift cards and useing them to fullfill my gasoline budget over the next month or two.  Just an idea if your going to purchase gasoline at Kroger anyway that would be a good way to stretch the old budget.