title: push-style notifications similar to Facebook with Rails and jQuery
body: <p>I want to create a push notification system like Facebook. Whenever Facebook wants to tell you something (like that someone commented on a post, tagged you, etc), you'll see a small notification show up in the bottom left corner of the screen. It fades in and fades out.</p>
  
  <p>How do I build a system like this with jQuery and Rails? How does it even work? Does JS constantly ask the server, "is there a new notification?" or does the server somehow <em>push</em> to this service.</p>
  
  <p>Right now, if a user sends another user a message (for example), I can add a notification to the user's queue saying "you have a new message", but it won't appear until a page reload... </p>