var currentpos=0,alt=1,curpos1=0,curpos2=-1
function initialize(){startit()}
function scrollwindow(){if (document.all)temp=document.body.scrollTop
else
temp=window.pageYOffset
if (alt==0)
/*alt=1
else
alt=0*/ /*esta parte faz com que volte para o topo.*/
if (alt==0)curpos1=temp
else
curpos2=temp
if (curpos1!=curpos2){if (document.all)currentpos=document.body.scrollTop+1
else
currentpos=window.pageYOffset+1
window.scroll(0,currentpos)}else{currentpos=0
window.scroll(0,currentpos)}}function startit(){setInterval("scrollwindow()",30)}
window.onload=initialize