During my corporate days, one of my requirements on every promotion we ran was that there was a way to share the promotion with a friend. For nearly every promotion, sharing was the number one referral to the promotion. The key was to make the act of sharing as easy as possible. Why is word of mouth marketing so important today?Today, having people share your content or service is even more important because competition for attention is stronger than ever. Yesterday I met with ShareThis CEO Tim Schigel. ShareThis provides a very simple way to add sharing to your website, ecommerce site or blog. One line of code added to your template is all that's needed to run the ShareThis widget. There are a number of players in the social sharing space including AddThis, AddtoAny and SocialTwist.

Here on InformationWeek, there are several ways to share content with others. The site has share buttons across the top of each article which include the ability to send the article to a friend, the AddThis widget and a Yahoo Buzz button. There is also a full page of sharing options for all of the InformationWeek content which is named "Take Us With You".

With the growth of instant messaging and social sites including Facebook and Twitter, only having an email option is no longer enough. All of the services I mentioned above allow you to share content and products on a large number of sources. What makes social sharing so powerful is that the sharing can grow exponentially. I share a piece of content with my network on Facebook, then several of those people share the content with their network, and so on.

Many of the customers at my startup have been sharing the service with their friends - but they have been doing it manually. This week I added the ability for my customers to share the service after they login. Already several customers have shared the service and we all know there's nothing better than a positive review from a friend.

I hope that you take a minute now and see if your products and content can be shared easily and effectively. There's just no reason not to reap the rewards of free marketing from your customers and readers.