Groupon has a great deal today for iTunes. You can get a $15 iTunes code for only $10. The sale is listed as four days, but I'm sure supplies will run out long before that.
Requires iTunes account and prior acceptance of license and usage terms. Must be 13+ and in the U.S. Compatible software/hardware/Internet access required. Codes are issued and managed by Apple Value Services, LLC (“Issuer”). Neither Apple nor Issuer is responsible for any loss or damage resulting from lost or stolen codes or use without permission. Apple and its licensees, affiliates, and licensors make no warranties, express or implied, with respect to code or the iTunes Store and disclaim any warranty to the fullest extent available. These limitations may not apply to you. Void where prohibited. Not for resale.