Код:
<SCRIPT LANGUAGE="JavaScript">           
var no = 50;         
var speed = 1;         
var ns4up = (document.layers) ? 1 : 0;         
var ie4up = (document.all) ? 1 : 0;         
var s, x, y, sn, cs;         
var a, r, cx, cy;         
var i, doc_width = 800, doc_height = 600;         

if (ns4up) {         
doc_width = self.innerWidth;         
doc_height = self.innerHeight;         
}         
else         

if (ie4up) {         
doc_width = document.body.clientWidth;         
doc_height = document.body.clientHeight;         
}         

x = new Array();         
y = new Array();         
r = new Array();         
cx = new Array();         
cy = new Array();         
s = 8;         

for (i = 0; i < no; ++ i) {         
initRain();         

if (ns4up) {         

if (i == 0) {         
document.write("<layer name=\"dot"+ i +"\" left=\"1\" ");         
document.write("top=\"1\" visibility=\"show\"><font color=\"blue\">");         
document.write(",</font></layer>");         

}         
else {         
document.write("<layer name=\"dot"+ i +"\" left=\"1\" ");         
document.write("top=\"1\" visibility=\"show\"><font color=\"blue\">");         
document.write(",</font></layer>");         
}         
}         
else         

if (ie4up) {         

if (i == 0) {         
document.write("<div id=\"dot"+ i +"\" style=\"POSITION: ");         
document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");         
document.write("visible; TOP: 15px; LEFT: 15px;\"><font color=\"blue\">");         
document.write(",</font></div>");         
}         

else {         
document.write("<div id=\"dot"+ i +"\" style=\"POSITION: ");         
document.write("absolute; Z-INDEX: "+ i +"; VISIBILITY: ");         
document.write("visible; TOP: 15px; LEFT: 15px;\"><font color=\"blue\">");         
document.write(",</font></div>");         
}         
}         
}         

function initRain() {         
a = 6;         
r[i] = 1;         
sn = Math.sin(a);         
cs = Math.cos(a);         
cx[i] = Math.random() * doc_width + 1;         
cy[i] = Math.random() * doc_height + 1;         
x[i] = r[i] * sn + cx[i];         
y[i] = cy[i];         
}         

function makeRain() {         
r[i] = 1;         
cx[i] = Math.random() * doc_width + 1;         
cy[i] = 1;         
x[i] = r[i] * sn + cx[i];         
y[i] = r[i] * cs + cy[i];         
}         

function updateRain() {         
r[i] += s;         
x[i] = r[i] * sn + cx[i];         
y[i] = r[i] * cs + cy[i];         
}         

function raindropNS() {         
for (i = 0; i < no; ++ i) {         
updateRain();         
if ((x[i] <= 1) || (x[i] >= (doc_width - 20)) || (y[i] >= (doc_height - 20))) {         
makeRain();         
doc_width = self.innerWidth;         
doc_height = self.innerHeight;         
}         
document.layers["dot"+i].top = y[i];         
document.layers["dot"+i].left = x[i];         
}         
setTimeout("raindropNS()", speed);         
}         

function raindropIE() {         
for (i = 0; i < no; ++ i) {         
updateRain();         

if ((x[i] <= 1) || (x[i] >= (doc_width - 20)) || (y[i] >= (doc_height - 20))) {         
makeRain();         
doc_width = document.body.clientWidth;         
doc_height = document.body.clientHeight;         
}         
document.all["dot"+i].style.pixelTop = y[i];         
document.all["dot"+i].style.pixelLeft = x[i];         
}         
setTimeout("raindropIE()", speed);         
}         
if (ns4up) {         
raindropNS();         
}         
else         
if (ie4up) {         
raindropIE();         
}         
</script>

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