Remember when Tom Cruise checked his email account in the first Mission Impossible movie?

A cool 3-D image shot out of his PC screen. Nobody had ever seen anything like it because in real life there was nothing like it ... until two movie fans got together to found IncrediMail.

Now, almost five years later, the service has more than 40,000,000 active users worldwide. What does this mean to the average email marketer? We interviewed VP Marketing Leeron Kuller to get some data for you:

Quick stats: Who are these 40 million active users?

"People who like to download fun software."

- Roughly 30% in the US (that's more than 13 million.) - 55% male - 40% ages 32-49 - Mainly home users and personal account users - Millions of Hotmail and AOL email users

Unfortunately no, you can't tell how many or which of the names on your list are IncrediMail users because the service is an add-on to a regular email account. So, users still have the same email address, but are using extra filters and various gizmos (more below) you're not tracking.

"Active" is defined as someone who has used the service within the last 60 days. (That's a tougher definition than most registered user lists we've heard of.)

Warning: What emailers need to know about IncrediMail's new filters

First things first -- IncrediMail launched spam filters September 28th. They are free and they are active in all accounts. Inevitably some permission-mail is going to get stuck in them.

Kuller assures us that the false positive rate is extremely low. But we've heard that before and don't completely trust it.

She notes that your mail will definitely get through to a recipient if you are whitelisted by that recipient. AOL and other whitelisting will not affect your status - you need to be whitelisted in the IncrediMail account as well.

Luckily whitelisting is automatic -- if a user sends you a message, that send-to address is added to their personal whitelist. (This is a concept we've heard from a few more filters recently -- definite trend material.)

As a mailer your job is three-fold:

#1. Keep your send-to/reply-to address stable and singular. If someone replies to an email you've sent and then you send from a different address, the new address isn't whitelisted.

#2. Ask names on your list to "reply" to you so the whitelisting takes effect. (Forget the click, get the reply first.) Perhaps you should run a special promo every quarter or so to get replies flooding in?

#3. Add an IncrediMail test account to the range of test accounts you already have to track your email delivery.

Aside from filters -- what do consumers use the service for (and how can it inspire your marketing campaigns?)

Since the free filter offer is new, the vast majority of users actually signed up for something else -- email excitement.

IncrediMail taps into a strong consumer urge to be able to be more creative, personal and fun with their email use than their current in-box allows them to be. This demonstrated urge alone is something we think email marketers should consider when dreaming up new campaigns and offers (especially viral ones.)

Users get two basic benefits in addition to the filter:

- Outgoing email creativity and personality: Users can add colors, cartoons, sounds, you name it, to their outgoing email messages. (Can you say involvement device?) They can choose options from a giant library, or create their own and offer them to other users in the library. (Can you say community?)

- Mailbox excitement: Users can choose any number of customized skin options to change what their mailbox looks (and acts) like. Plus, they can have cartoon characters leap out of the desktop to alert them when there's new mail. (No, none of the characters are branded now, but they could be...)

We suggest you ask your email creative team to brainstorm a bit on how you could take advantage of these concepts (regardless of whether you ever partner with IncrediMail to access their users).

Perhaps we've all become a bit too staid in our "get the standard campaign out on schedule" world. Perhaps users would be thrilled to get something really different from us.

Viral heaven: how these guys get one million new sign-ups a month (without advertising)

Yes, they do the whole Hotmail thing of adding free offer SIGs to outgoing free users' messages. However, they take viral SIGs to the next level by giving users a variety to choose from so it's less generic, and by constantly tracking and optimizing the SIG creatives on offer. (Link below to a few samples.)

Plus, they do the whole email newsletter please-pass-it-on thing. (Link to samples below.) Kuller notes the newsletter team is extremely careful to keep marketing and sales messaging close to non-existent within the content.

"We offer very cool little tips and tricks and tell them about other free partnerships. It's very non-advertising oriented. They love it. If they get off the list by mistake, they email us 'How do I get back on again?'"

And then there are the Webrings.

Very few brands outside of Hollywood can boast voluntary Webrings of fan sites dedicated to the brand's glory ... except IncrediMail.

The marketing team knows how lucky they are, and courts the Webring community by listing links in a site library, and announcing new Webrings on request in each issue of the newsletter. "It's a pretty long list, and within each ring you've got hundreds of sites," notes Kuller.

IncrediMail's profitable business model & partnership opportunities

"We've been profitable for quite a while," notes Kuller. How? IncrediMail turned down advertising for several years, and now accepts a bit on a CPC basis. ("We haven't done any aggressive seeking.")

Instead the service is largely user-supported. Users can upgrade to their choice of a few different premium-level offerings for one-time flat fees ranging from $29.95-49.95. These are lifetime fees -- not subscriptions. (This shocked us slightly, but Kuller says the new user pool expands so much each month that management's never fretted about creating an annuity income stream.)

Instead, the team is currently focusing on partnerships to create new free services with premium upsells. So far they've joint ventured to launch IncrediDate and IncrediGames. "We provide the users and trusted name, and partners provide the platform." Kuller says they're interested in hearing from content-side folks who can power a horoscope site or something else of "global interest."

She also admitted -- but only after we pushed her -- that the company might be open to allowing a few sponsored characters or creatives into the user library. Global brands only please.

Useful links related to this article:

Samples of various IncrediMail newsletters, viral SIGs, etc: http://www.marketingsherpa.com/incredimail/ad.html

Related MarketingSherpa article -- Quick Primer: How to Advertise on Instant Messaging Skins http://www.marketingsherpa.com/sample.cfm?contentID=2832

IncrediMail http://www.incredimail.com