So you think the accompanying picture is mysterious, or worse, boring? I agree. But it may prompt you to look at an update of one of my “on-line experiments on  #visualperception ":
      It demonstrates the Flash Lag Effect (an #opticalillusion ) in a new way, which I find lots stronger than the previous version (which you can see when selecting “Disk”). 

  This is my New Year contribution. Will not mention my resolutions, since they'll evaporate anyway :).