残像をつけて、マウスと共に移動する文字列を表示する      
Sample
マウスを動かしてください。

ソース
<HTML>
<HEAD>

<SCRIPT LANGUAGE="JavaScript">
<!--
message = 'Java-Da!!';
font_name = 'century';
color_name = 'skyblue';
font_size = 4;

var amount = 5, m_ypos =- 50, m_xpos = 0, Ayp = 0, Axp = 0, Byp = 0,
 Bxp = 0, Cyp = 0, Cxp = 0, Dyp = 0, Dxp = 0, Eyp = 0, Exp = 0;
if (document.layers) {
  for (i = 0; i < amount; i++) {
    document.write('<layer name=nsl'+i+' top=0 left=0><font face='+font_name+
' size='+font_size+' color='+color_name+'>'+message+'</font></layer>');
  }
  window.captureEvents(Event.MOUSEMOVE);
  function nsmouse(_evnt) {
    m_xpos = _evnt.pageX + 20;
    m_ypos = _evnt.pageY + 20;
  }
  window.onMouseMove = nsmouse; 
} else if (document.all) {
  document.write("<div id='outer' style='position:absolute;top:0px;left:0px'>");
  document.write("<div style='position:relative'>");
  for (i = 0; i < amount; i++) {
    document.write('<div id="text"'+i+
' style="position:absolute;top:0px;left:0px;width:400px;height:20px"><font face='
+font_name+' size='+font_size+' color='+color_name+'>'+message+'</font></div>')
  }
  document.write("</div>");
  document.write("</div>");
  function ie_mouse() {
    m_ypos = event.y + 5;
    m_xpos = event.x + 5;
  }
  window.document.onmousemove = ie_mouse;
}
function makefollow() {
  if (document.layers) {
    document.layers['nsl'+0].top = ay;
    document.layers['nsl'+0].left = ax;
    document.layers['nsl'+1].top = by;
    document.layers['nsl'+1].left = bx;
    document.layers['nsl'+2].top = cy;
    document.layers['nsl'+2].left = cx;
    document.layers['nsl'+3].top = Dyp;
    document.layers['nsl'+3].left = Dxp;
    document.layers['nsl'+4].top = Eyp;
    document.layers['nsl'+4].left = Exp;
  }
  else if (document.all) {
    outer.style.pixelTop = document.body.scrollTop; 
    text[0].style.pixelTop = ay;
    text[0].style.pixelLeft = ax;
    text[1].style.pixelTop = by;
    text[1].style.pixelLeft = bx;
    text[2].style.pixelTop = cy;
    text[2].style.pixelLeft = cx;
    text[3].style.pixelTop = Dyp;
    text[3].style.pixelLeft = Dxp;
    text[4].style.pixelTop = Eyp;
    text[4].style.pixelLeft = Exp;
  }
}
function move() {
  ey = Eyp += (m_ypos - Eyp) * 0.2;
  ex = Exp += (m_xpos - Exp) * 0.2;
  dy = Dyp += (ey - Dyp) * 0.3;
  dx = Dxp += (ex - Dxp) * 0.3;
  cy = Cyp += (dy - Cyp) * 0.4;
  cx = Cxp += (dx - Cxp) * 0.4;
  by = Byp += (cy - Byp) * 0.5;
  bx = Bxp += (cx - Bxp) * 0.5;
  ay = Ayp += (by - Ayp) * 0.6;
  ax = Axp += (bx - Axp) * 0.6;
  makefollow();
  setTimeout('move()', 10);
}
window.onload=move;
//-->
</SCRIPT>

</HEAD>
<BODY>
</BODY>
</HTML>
ワンポイント解説
message = 'Java-Da!!'; で、表示する文字列を設定しています。