Somehow I knew you were going to ask that
Originally Posted by daemon
Now that's a much more complicated matter! You have to absolutely position the element (50%,50%) containing the image and then give it minus margins (at half of the dimensions). So the height of the image is 110 (I give the block a -55 top margin), the width is 276 (I give it a -138 left margin).
<body style="text-align: center; margin: auto;">
width="276" height="110" /></a>