You can fit the strategies that Michael is speaking of into a number of other businesses. In fact, I'm always surprised the lack of email strategy by tech companies.
When a user comes to your site, there are methods of introducing him to your product that isn't a hard-sell "You need this product--sign up now." You need to introduce them to your product before you make a sale.
So you can offer a giveaway that entices a user join a newsletter. Then you send interesting emails---emails that a reader appreciates being sent. The kind they actually read till the end, and think it was a good decision to read. This builds trust.
But the next step? You introduce them your product, show them why they will get a benefit from it, and then offer them the product---and because they trust you, and understand where it comes from, the user will be likely to buy it.
I'm working on something similar with RescueTime---introducing users to the product with a more story-telling angle.