The IE double float margin bug shows up in practically every floated CSS layout. If there is a floating element with a margin value, its margin will be doubled in IE6. To fix this behaviour, simply set the floated element's display property to inline. Here is a short example that uses the "Star HTML Hack":

#element {
    float:left; margin:10px;
}
* html #element {
    display:inline; /* IE only */
}