This script will open a floating Layer popup. The layer stays on top, allowing the user to work in the main window while still being able to view the popup. The popup window stays in the same place, even when the user scrolls down the page. It also works with image maps.
In the source code you see return false and target='_self"'. These are measures are to Prevent unwanted behavior when the base target is set to _blank or when you want to provide the user with an alternative link in case JavaScript isn't turned on in the user's browser.