Viral marketing is the old-fashioned "word of mouth" concept, wired-up and electrified for the Internet Age. Compare a Mexican Wave with the old game of Chinese Whispers and you'll see the difference. It's not a message being passed down the line one person at a time, it's a tidal wave that spreads and rushes across a crowd. Think of all those emails you see from friends and colleagues passing around the latest joke or outrageous video. Have you ever forwarded one? They spread like a virus, and when they are deliberately created to promote a product, that's when they become viral marketing. How can you do that for your business?

Viral marketing works on different levels. The video clip, for example, being mass circulated via email is the pinnacle of achievement but hard to succeed at because people are very subjective about what they find amusing or entertaining. On another level, you might create a work with intrinsic value, an article or a report for example, which people find interesting and pass on to their friends and colleagues in case it is useful. That's easier to do because the test is whether the subject matter is good and relevant. Both of those levels require positive actions to progress, that is, each person in the chain must deliberately choose to forward it, but there is another level that works in a passive way.

Social and business networking sites are all the rage right now, MySpace, YouTube, Facebook and Bebo for the social side, and LinkedIn and Plaxo for the business side, are the market leaders that most people will be familiar with. Passive viral marketing works when users include information about you or your products or services in their own profile or listings which will be seen by their friends, colleagues and contacts. It is slow-burning compared with the high-octane level of spread that a hot new video will achieve, but over time it could spread the word just as far and wide, or at least to those who need to know.

Facebook is worth a closer look because it is making an active effort to bridge the gap between social and business networks. You can create a presence on Facebook, a "Fan Page" as they term it, for your business, or perhaps more effectively for some aspect of your business. You populate that page with useful information, images, videos, etc, and anyone can sign-up as a "Fan". Those who do will have that fact reported in their own profiles and news feeds to be seen by all their Facebook Friends in turn, as well as appear in any search results. Your fans will see a new item in their news feed each time you update your fan page with news or more material, so you have a ready-made opportunity to kick-start a viral marketing campaign every time. However, the onus is on you at all of these levels to create material that will generate interest or it simply won't become viral.

For the sake of completeness, let me also mention that you can "spread the word" yourself by posting comments to blogs and forums, and while that can be a very effective marketing ploy which I do recommend, isn't strictly speaking "viral" because you're doing it yourself and in this blog I just wanted to stick to viral marketing per se.

So given all that, what could you realistically do to have a go at viral marketing?

The viral video.
Unless you are a professional comedian, actor, musician or producer, the chances of you sitting down and creating a video that millions of people will find amusing or entertaining enough to pass round to their friends is pretty slim. That's not to say there are plenty of home videos that do the rounds, the point is they are generally accidental. Big businesses with deep pockets work this end of the market. Take Honda and their two minute one-take video of all those car parts dominoing into one another. That is reputed to have cost six million dollars to make. There are at least five copies of that ad on YouTube with a total viewing figure of more than 2.5 million. Another big hit was the Cadbury's chocolate one with a man in the gorilla suit drumming to a Phil Collins song. There are literally hundreds of versions of that ad on YouTube, with the most popular one being viewed more than two million times.

Creating something with intrinsic value.
Realistically, this is probably your best bet. Good, useful, reliable information is always sought after and a pdf document - or even a blog - on some topic can always strike a chord and be passed around. Or run a poll or conduct a survey and publicise the results.

Social networking.
Sign-up on all the social and business networking sites you can tolerate. Post content and network with the people on them, spread your name far and wide.
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