<style>
.blocks1 { 
    background-image:url(http://forum.antichat.ru/antichat/pic/logo.gif); 
    background-position:left; 
    background-repeat:no-repeat; 
}
.blocks2 { 
    background-image:url(http://forum.antichat.ru/antichat/pic/logo.gif); 
    background-position:right; 
    background-repeat:no-repeat; 
}
</style>
<div class="blocks1" style="width:600px; height:100px;"><div class="blocks2" style="width:600px; height:100px;"></div></div>