The deal can be found here. When you get to the site, you click on the "Redeem Now" button to activate the deal.
That's where the interesting part comes in. When you click the "Redeem Now" button you get a 16-digit personalized code. The code is not valid in-store, but shipping is free for purchases over $20. As you might expect, Staples charges sales tax in most locations.
The coupon is one of the few that appears to work on all items, including electronics, at Staples.
The use the coupon, you copy the 16-digit coupon code, then use it when checking out. As an alternative, Staples says customers can call 1-800-333-3330 and place the order with a representative. There, you would tell the customer service representative serving you your 16-digit coupon code.
For those who run afoul of the "dang I have $99.99 in my cart" issue, a filler -- such as this one -- can be used to push you over the top.