At the register, it should print out a Staples Easy Rebate valid for a $25 Prepaid Card.
Go home and submit the rebate.
You can do this by going to StaplesEasyRebates.com and enter the item number of the above Western Digital drive into the SKU/UPC box.
For example, if you bought the 1TB drive, enter its item number 86377.
A $25 Rebate Prepaid Card should appear, valid with a purchase date between January 4 and January 31.
Follow the instructions to submit the rebate online.
As per the terms of the rebate, this deal is only available with an in-store purchase.