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More often than not, the greatest challenge facing a webmaster has little to do with the technology running her web site. The biggest challenge is providing enough different content quickly enough so that her clients keep coming back to the site and keep telling others about the site. Clients today have millions of sites to choose from—often several hundred on any given subject. Why frequent yours if the content doesn't change often enough to make the few clicks it takes to get there worth the effort?
One solution to this problem is to provide, on a regular basis, a small change to your web site or its more popular pages. This small change—if clever or original enough—can keep a user on the site just long enough for him to see something that he may not have seen before—even if the content in question has been present for some time. More important, for some sites this change could keep the user long enough to notice an advertisement and click on it.