Use a Digsby widget in your sidebar, on a page or post or by a link to use a pop up with the Digsby widget inside.
<?php wpDigsbyDisplay("width", "height");?>
(Width and Height can be px or %). 3. You can add the chat window to a page or post ([[DIGSBY]]). 4. You can add a link anywhere by using the code
where YourTitle is the title of the window that will open with your chat window.