You can use a combination of JavaScript and CSS to make what looks like a window (but is actually a block-level HTML element on the same page) appear/disappear much like an actual window. Basically the element in question has it's initial CSS "display" property set to "none". Then you use JavaScript upon the desired trigger to change the "display" value to "block". You also use CSS to make that element "position: absolute" along with the "top", "left", "right", and/or "bottom" properties to control where it is positioned on the page. You can then use a link, icon, etc. with an onclick event that sets the display value back to "none" when you want to close that pseudo-window.