We probably wont be writing our own CSS Behaviors for IE6+, however it looks like they can be used for a number of neat things to fix IE.<p>Below are examples of using IE's CSS Behaviors to fix border radius and png transparencies.<p>http://www.htmlremix.com/css/curved-corner-border-radius-cross-browser<p>http://scarfoo.com/archives/16<p>http://www.twinhelix.com/css/iepngfix/<p>http://msdn.microsoft.com/en-us/library/ms532147(v=vs.85).aspx<p>http://msdn.microsoft.com/en-us/library/ms531078(v=vs.85).aspx<p>http://msdn.microsoft.com/en-us/library/ms531079(v=vs.85).aspx