Usually, it takes a great deal of work and resources to increase advertising effectiveness. But every once in a while a simple tip can yield impressive results. Here's one:

Much has been written about "banner blindness" - the tendency of Internet users to ignore anything in a rectangle at the top of a Web page. This is because Web banners tend to distract users from achieving their goal at a site: obtaining information, making a purchase, etc.

However, research has shown that the moment of opportunity comes immediately after users have satisfied their primary reason for visiting. At that moment, the user is "vulnerable" to advertising messages. He or she is not sure what to do next, and may be open to suggestions. Assuming that the site has served users' objectives, it's also likely they are somewhat favorably disposed toward the site or the company.

Unfortunately, it is at this point that most Web sites fail. Many sites leave visitors with only a navigation bar or a "thank you," rather than offering options for what to do next. Sites should borrow from the "upsell" techniques that have been used offline for years. Consider what the user has accomplished and what she might like to do next. For example, after a purchase, it might be appropriate to offer links to complementary items ("did you know that we also offer...") or advertising for sites with relevant information.

Remember, any advertising is more likely to get noticed on the "thank you" or "results" page rather than the Home page, since users have already accomplished their goal and are more willing to divert their attention.