To include this FX in your document you need to put the the following in the HEAD section of your document

<!-- *** BEGIN CUT - Start Code *** -->
<!-- (* Another free JavaScript from JavaScript-FX.com *) -->
<SCRIPT LANGUAGE="javascript" SRC="javascript/JSFX_Layer.js"></SCRIPT>
<SCRIPT LANGUAGE="javascript" SRC="javascript/JSFX_Mouse.js"></SCRIPT>
<SCRIPT LANGUAGE="javascript" SRC="javascript/JSFX_FadingTrail.js"></SCRIPT>
<SCRIPT LANGUAGE="javascript" TYPE="text/javascript">
<!--
function JSFX_StartEffects()
{
      JSFX.FadingTrail(80, '00FF00', '000000', 0);
}
//-->
</SCRIPT>
<!-- *** END CUT - End Code *** -->

Put the following in the BODY TAG of your document

<BODY onLoad="JSFX_StartEffects()">

Customization.
Param1: "80" - The number of "elements" in the Fading Trailer (10-80).
Param2: "00FF00" - Any valid Hex HTML color ("FFAACC", "000000", etc...).
Param3: "000000" - Any valid Hex HTML color ("FFAACC", "000000", etc...).
Param4: 0 - The type of trailer (The only valid values are - 0, 1, 2, 3)

Also See...
Using External ".js" Files
Combining Multiple Scripts.