String.prototype.rot13 = function(){ //v1.0
	return this.replace(/[a-z%A-Z]/g, function(c){
    if(c=='%') return "@";
		return String.fromCharCode((c <= "Z" ? 90 : 122) >= (c = c.charCodeAt(0) + 13) ? c : c - 26);
	});
};

function mail(x) {
  document.location = "mailto:"+x.rot13();
}