<script>   
var fs=1   
var direction="right"   
function rollertext(whichone){   
var thetext=whichone   
for (i=0;i<thetext.length;i++){   
document.write(thetext.charAt(i).fontsize(fs))   

if (fs<7&&direction=="right")   
fs++   
else if (fs==7){   
direction="left"   
fs--   
}   
else if (fs==1){   
direction="right"//osw   
fs++   
}   
else if (fs>1&&direction=="left")   
fs--   

}   
}   

rollertext("Тут пишите свой текст")   
</script>