The folks at PETCO  tested an email registration overlay ad that helped lift subscriptions more than 400%.

Carol Ott, Director, Finance Reporting and Web Analytics, PETCO, and the team used Amadesa’s Customer Experience Suite to A/B test the ad (and other offers) on the homepage since June.

As you can see in the image below (click for a larger one), the overlay offers visitors two rewards for submitting email addresses:
1. Chance to win a $500 gift card
2. A free shipping offer

“We were impressed with the results. We were testing offers that we thought would drop our average order value and were pleasantly surprised when it did not have any effect,” Ott says.