var sizes = new Array("0px", "1px", "2px","4px", "8px");
sizes.pos = 0;
function rubberBand()
{
var el = document.all.welcom;
if (null == el.direction)
el.direction = 1;
else if ((sizes.pos > sizes.length - 2) ||
(0 == sizes.pos))
el.direction *= -1;
el.style.letterSpacing = sizes[sizes.pos += el.direction];
}