This is what I would do:
//inside <head> leavingSite = false; window.onunload = function(){ leavingSite = true; setTimeout("if(leavingSite){ [insert ajax] }",2000); } If the new page does not load in 2 seconds or the user left the site, then the script will execute. (although I'm not sure what will happen if they close the browser) Keep in mind I haven't tested this code yet, so give it a go. ~Sean