Avoid popup windows. Extra windows keep users from getting to your site content, and even if such windows contain valuable information, users are likely to dismiss them immediately as ads. Instead, put critical information in a highly noticeable area of the homepage. The other drawback to popup windows is that they go away — once the user gets rid of them, they're gone, so users often can't find the information again even if they want to. It's better to design your homepage to give high priority to critical content.