Fantasmas en el blog

Ponerlo en el blog es sumamente sencillo, sólo basta entrar en Diseño | Elementos de la página | Añadir gadget | HTML/Javascript y ahí pegar este código:

<script language="JavaScript">
if ((document.getElementById) &&
window.addEventListener || window.attachEvent){
(function(){

//Configuracion

var numberOfGhosts = 10; /* Numero de fantasmas */
var ghostSpeed = 0.9; /* Velocidad */
var inTheFace = 5;
var setTimeOutSpeed = 50; /* Velocidad a la que desaparecen */

//Fin de la configuracion

var h,y,cy,cx,sy,sx,ref,field,oy1,oy2,ox1,ox2,iy1,iy2,ix1,ix2;
var d = document;
var domWw = (typeof window.innerWidth == "number");
var domSy = (typeof window.pageYOffset == "number");
var pi1 = 180/3.14;
var pi2 = 3.14/180;
var y = [];
var x = [];
var strs = [];
var gro = [];
var dim = [];
var dfc = [];
var vel = [];
var dir = [];
var acc = [];
var dtor = [];
var xy2 = [];
var idx = document.getElementsByTagName('div').length;
var zip = [];
var pix = "px";

for (i = 0; i < numberOfGhosts; i++){
document.write('<div id="ghosts'+(idx+i)+'"'
+' style="position:absolute;top:0px;left:0px;'
+'width:40px;height:40px;background-color:transparent;'
+'font-size:0px;"><img src="http://1.bp.blogspot.com/_dsEG33PDaHw/TLUwy8cYCsI/AAAAAAAAAZ0/kWv1B3tlak4/s1600/ghost.gif" class="ghost" width="70"/></div>');
}

if (domWw) ref = window;
else{
if (d.documentElement &&
typeof d.documentElement.clientWidth == "number" &&
d.documentElement.clientWidth != 0)
ref = d.documentElement;
else{
if (d.body &&
typeof d.body.clientWidth == "number")
ref = d.body;
}
}

function win(){
var mozBar = ((domWw) &&
ref.innerWidth != d.documentElement.offsetWidth)?20:0;
h = (domWw)?ref.innerHeight:ref.clientHeight;
w = (domWw)?ref.innerWidth - mozBar:ref.clientWidth;
cy = Math.floor(h/2);
cx = Math.floor(w/2);

oy1 = (75 * h / 100);
oy2 = (oy1 / 2);
ox1 = (75 * w / 100);
ox2 = (ox1 / 2);

iy1 = (18 * h / 100);
iy2 = (iy1 / 2);
ix1 = (18 * w / 100);
ix2 = (ix1 / 2);

field = (h > w)?h:w;
}

function rst(s){
var cyx;
sy = (domSy)?ref.pageYOffset:ref.scrollTop;
sx = (domSy)?ref.pageXOffset:ref.scrollLeft;
acc[s] = 0;
dim[s] = 1;
xy2[s] = 0;
cyx = Math.round(Math.random() * 2);
if (cyx == 0){
y[s] = (cy - iy2) + Math.floor(Math.random() * iy1);
x[s] = (cx - ix2) + Math.floor(Math.random() * ix1);
}
else{
y[s] = (cy - oy2) + Math.floor(Math.random() * oy1);
x[s] = (cx - ox2) + Math.floor(Math.random() * ox1);
}
dy = y[s] - cy;
dx = x[s] - cx;
dir[s] = Math.atan2(dy,dx) * pi1;
dfc[s] = Math.sqrt(dy*dy + dx*dx) ;
zip[s] = 10 * (dfc[s] + inTheFace) / 100;
vel[s] = ghostSpeed * dfc[s] / 100;
dtor[s] = (field - dfc[s]);
if (dtor[s] < 1) dtor[s] = 1;
gro[s] = 0.003 * dtor[s] / 100;
}

function animate(){
for (i = 0; i < numberOfGhosts; i++){
y[i] += vel[i] * Math.sin(dir[i] * pi2);
x[i] += vel[i] * Math.cos(dir[i] * pi2);
acc[i] = (vel[i] / (dfc[i] + (vel[i] * zip[i])) * vel[i]);
vel[i] += (acc[i]);
dim[i] += gro[i] + acc[i] / zip[i];
xy2[i] = dim[i] / 2;
if (y[i] < 0 + xy2[i] ||
x[i] < 0 + xy2[i] ||
y[i] > h - xy2[i] ||
x[i] > w - xy2[i]){
rst(i);
}
strs[i].top = (y[i] - xy2[i]) + sy + pix;
strs[i].left = (x[i] - xy2[i]) + sx + pix;
strs[i].width = (strs[i].height = (Math.round(dim[i])) + pix);
}
setTimeout(animate,setTimeOutSpeed);
}

function init(){
win();
for (i = 0; i < numberOfGhosts; i++){
strs[i] = document.getElementById("ghosts"+(idx+i)).style;
rst(i);
}
animate();
}

if (window.addEventListener){
window.addEventListener("resize",win,false);
window.addEventListener("load",init,false);
}
else if (window.attachEvent){
window.attachEvent("onresize",win);
window.attachEvent("onload",init);
}
})();
}//End.

</script>

<style>
.ghost {
filter:alpha(opacity=30);
-moz-opacity: 0.3;
opacity: 0.3;
-khtml-opacity: 0.3;
}
html {
overflow-x:hidden;
}
</style>

Con eso ya tendrán los fantasmas merodeando el blog. Se pueden modificar algunos valores de velocidad al gusto, esos se modifican en las anotaciones que he puesto en color verde.

NOTA: En las plantillas del diseñador de Blogger no funciona muy bien. Raro ¿no?