var tags = new Array('div','td','tr','p','b','span','table','strong','emphasis','a','h1',
'h2','h3','pre','sub','sup','i','th','cp','ul','ol','li','dt','dd');
 var pixelArray = new Array('7','8','9','10','12','15','18');
var emArray = new Array('0.7','0.9','1.0','1.5','2.0','2.5','3');
   var initSize = 3;
            
function fontSizer(inc,unit) {
if (!document.getElementById)
return;
var size = initSize;
size += inc;
if (size < 0 ) {
size = 0;
}
if (size > 6 ) {
size = 6;
}
initSize = size;
getBody = document.getElementsByTagName('body')[0];
for (i = 0 ; i < tags.length ; i++ ) {
getallTags = getBody.getElementsByTagName(tags[i]);
for (k = 0 ; k < getallTags.length ; k++)
getallTags[k].style.fontSize = (unit=='px') ? pixelArray[size]+unit: emArray[size]+unit;
}
}