Very Short Pop Up Flash Sale
Why?
Help convert the ones who are just a step before buying.
How?
When a visitor seems to be interested in an item (he spent more than average time on that page, scrolling back and forward reading, etc.), but then seemed to not buy the item and move on to something else (still on your website), you can pop up a one time offer that has a very short time limit (one minute should be more than enough.) It might say something like this: “Get XYZ for $79 instead of the usual $139 price. This offer is only good if you add it to your cart within the next 00:48 seconds.” (The time is an active countdown.) Once it’s in the cart, it should have a small text saying that the discount is only valid if they buy it during their current visit. This will help keep them from abandoning the cart and not finishing the purchase.