At the latest summit, wrapping up today, presenters discussed Papa John's email case history. One of the more insightful companies looking to grow its list, which already stretches into the millions, Papa John's is the one with the "Better Ingredients, Better Pizza" tagline, fronted in commercials by its boisterous founder.

Consider some of the out-of-the-pizza-box tactics it has developed to garner as many addresses as possible. In a pilot program, customers can effectively exchange an email address for a discount (sent via email to verify the address, of course) at in-store computers, as they wait to pick up a Hawaiian BBQ Chicken pie.

The company has also used a Facebook fan page to grab addresses. It has 293,000 fans. Some 130,000 of those came in the initial 24-hour period after launch, and 75% handed over an email locale, as there was an offer for a free pizza.

In 2009, the company wants to find ways to use text messaging to collect more addresses, though its executive overseeing online marketing acknowledges people hold their mobile devices dear and may view them as a marketing-free zone, so caution is required.

It may not be long before Papa John's asks its delivery team to ask for an email address in lieu of a tip -- and then pay the gratuity to its employees itself.

It's interesting how willing to receive -- or at least not opt-out of -- Papa John's emails people seem to be. The company sends out two a week to its full database offering a variety of specials.

In about 10 days, ExactTarget, the Email Marketers' Club and the Center for Media Design at Ball State University will publish a survey where marketers rated 18 list-growth strategies based on ROI and two other criteria. They were also asked what they may do differently next year.

Key findings, according to Morgan Stewart of ExactTarget, include "on-site registration tactics are the clear winners" and "social forwarding and mobile capture will be the most adopted new tactics in the year ahead."

Count on Papa John's to add a few new ones to the 18 by the time the 2010 survey comes out. It's hungry.

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