====== IE z-index bug ======
In short, z-index is broken in IE compared to other browsers because IE starts positioned elements with z-index 0.  The fix is to make the parent of the positioned element have a z-index at least 1 higher.

===== External Links =====
  * http://www.quirksmode.org/bugreports/archives/2006/01/Explorer_z_index_bug.html
  * http://tjkdesign.com/articles/z-index/teach_yourself_how_elements_stack.asp