Use following code to show a div as band in top-left corner.
See used example here:
I used thjs in following blog: http://piczseries.blogspot.com/
And this Orkut Application: http://www.orkut.co.in/Main#Application?appId=768834514623
<div style="position: absolute; top: 75px; left: -225px; width: 600px; padding: 10px; font-size: 24px; text-align: center; color: rgb(255, 255, 255); font-family: 'trebuchet ms',verdana,arial,sans-serif; -moz-transform: rotate(-45deg); -moz-transform-origin: 50% 0pt; background-color: rgb(0, 0, 0); border: 1px solid rgb(170, 170, 170); z-index: 12; opacity: 0.5;">Hi there!</div>
