I’ve found 14 so far:

Please drop me a line if you find any more. In each of them Marco and Marko are dressed in the team colours appropriate for the side they say they’re supporting, but they’re also wearing identical green German-style hunter’s hats. The mystery deepens, but not for long…

In small print at the bottom of each of the above sites, it says in Dutch: ‘Are you Dutch and can’t figure out what this is all about? Click here.' If you do, you’re taken to www.geheimwapen.nl (‘secret weapon’) where, if you answer an absurdly easy multiple-choice question to check your status as a real Lowlander, you receive the following message: ‘Congratulations. You’re a real Oranje fan. We, Marco and Marko, are working on a secret operation. An operation about the World Cup that we can’t say anything about at the moment. So keep your mouth shut, OK? Leave your name and e-mail address and we’ll keep you informed.”

Now check out the similarity between Marco and Marko’s green and orange hunter’s hats and the photo above that was ‘leaked’ last week. If you take the top off the pointed hat, you have a ‘megaphone’ with a Heineken logo down the side, leaving the bottom half as the same hats worn by our intrepid secret agents. Once again, Heineken seem to be hot on the trail of the most successful World Cup premium.

One of the things I’ve learned – and relearned, a few times – in my 24 years in the Netherlands is that nothing ignites the firework of national rivalry between the Dutch and the Germans better than football. With the World Cup around the corner, new viral marketing campaigns in each country have just lit the blue touch paper. Now their authors – and their clients – are standing well back to collect a free promotional bonanza from football fans. I think you’ll agree they’re both excellent examples of the communicative art of multimedia viral marketing. And having come into contact with the virus, here am I doing my bit to spread it. But I’m also bringing them to your attention because they’re both extremely entertaining.

In keeping with World Cup tradition, I’ll start with the hosts: Arno Lindemann and Peter Kabel, representing two Hamburg agencies of the brilliantly creative Jung von Matt group. In a provocative campaign for Electronic Arts’ official FIFA World Cup 2006 computer game, they’ve created a teaser TV spot showing Dutch fans celebrating Holland having won the World Cup, drowning the centre of Berlin in a sea of orange.

IWithout mentioning the client or product, the teaser directs the audience to www.hollandstoppen.de. Print ads in sports and special interest magazines with the heading ‘Holland are World Champions!’ also direct readers to the site, but the majority of visits will undoubtedly be encouraged by buzz. Longer spots can be run on the ‘Stop Holland’ site, and there are a number of great features, such as a condolence book and a multimedia phrase book to teach German fans how to insult their Dutch counterparts in their own language. And you can even find out about the computer game there too if you like.

As Oranje are ranked third in the world, the Dutch are not to be outdone of course. Over the last few weeks a pair of Dutchmen called Marco and Marko – one of whom, bizarrely, the spitting image of a younger Harry Enfield – have mysteriously been setting up websites. Short films run on the sites with Marco and Marko (Eminem?) purporting to actually be supporters of national teams other than Holland.

The sixth Client & Partner Briefing questioned the value of top-level domain real estate on the Internet.

The fifth Client & Partner Briefing argued that propaganda was replacing informed and informative PR in the European technology patents debate.

Our fourth Client & Partner Briefing looked at the communication of corporate citizenship - the value in values.

In the third Client & Partner Briefing we discussed the blogging phenomenon and the rise of the corporate weblog.

The second Client & Partner Briefing presented our views on why 80% of CRM projects have failed in the Netherlands.

Our first Client & Partner Briefing addressed the thorny question of whether or when -ise or -ize word endings should be used.