function playVideo(id, count) {
for (i = 1; i <= $('events_tr').value; i++) {$("eventvideo"+i).update("");}
new Ajax.Request('/_incs/ajax_eventvideo/'+id,
  {
    method:'get',
    onSuccess: function(transport){
      var response = transport.responseText || "no response text";
$("eventvideo"+count).update(response);
    },
    onFailure: function(){ $("eventvideo"+count).update("Eek! couldn't load video."); }
  });
}