Copy to Clipboard (Simple w/ Tutorial)
Simple clean project that enables Copy-to-Clipboard functionality with simple JQuery code. Project also has a tutorial to show you how easy it is to use and change values yourself with ease.
A simple use case would be as you see here with a nice Coupon Card (maybe as a popup) to engage your visitors as they shop with a little incentive to convert sales.
Up to you to be creative :)