document.onkeydown=NavigateThrough;

var site1=return_services(homepage);
var site2=return_services(homepage+","+site1);
var site3=return_services(homepage+","+site1+","+site2);

function NavigateThrough(a){
	if(!document.getElementById)
	return;
	if(window.event)
	a=window.event;
	if(a.ctrlKey){
		var b=null;
		switch(a.keyCode?a.keyCode:a.which?a.which:null)
		{
			case 0x25:b=document.getElementById('ctrl_left');break;
			case 0x27:b=document.getElementById('ctrl_right');break;
			case 0x28:open_slide();break;
			case 0x26:open_slide();break
		}
		if(b&&b.href)
		document.location=b.href
	}
}