Starbucks is offering $1 Off ANY Espresso Beverage with this coupon. You can either print it off or show the email to the barista on a mobile device.
Source: $1 Off Starbucks Coupon Email
For a limited time enjoy a Caramel Macchiato or any espresso beverage for $1 off. Through 1/20/13 at participating stores.
For more Starbucks deals, click here.