http://www.htmlcodetutorial.com/link...amsupp_70.html
I think you can get the pop-up shown in the above link to fire automatically when you open the page by using <body onLoad="return popup(this, 'notes')">
Rackspace.com's popup (except for the "x" close image) seems to just be one big link to it's live chat interface. Here's a link to the (free) live support chat I've easily integrated into a site. I'm very happy with the free version.
http://www.volusion.com/livechat_sof...sp?click=45812