Fluid Two DIV Layout
HTML
<div id="content_shell">
<div id="right_rail">
<b>Right</b>
</div>
</div>
<div id="left_rail">
<b>Left</b>
</div>
<div id="filler_rail"></div>
CSS
#content_shell{
float: left;
width: 100%;}
#right_rail{
margin: 0 1px 0 50%;}
#left_rail{
float: left;
width: 50%;
margin-left: -100%;
background: #C8FC98;}
#filler_rail{
float: left;
width: 1px;
margin-left: -1px;}