The glyphs for this episode spell out: MULTI
Walter, flying his kite, defies the storm saying, "Strike me down you sprites, you elves, you glorious blue jets ". The lightning we normally see is an electric discharge between a cloud and the ground. In 1989, for the first time, electrical discharges were recorded between the tops of storm clouds and the ionosphere. The most common upper atmosphere lightnings are 'red sprites', 'ELVES', and 'blue jets'.
The Observer walks on the sidewalk behind Peter after his expensive taxicab ride to New York.
The running joke of Walter having difficulty remembering Astrid's name is used again. This time he calls her "Ostrich".
There is a reference to the Baghdad Museum. When the U.S. invaded Iraq the infrastructure of that country quickly collapsed, primarily because of workers abandoning their posts. This also applied to the police and even to museum guides. At the time the Baghdad Museum contained the world's largest collection of ancient Middle Eastern artifacts. Thanks to the absence of guards, thieves broke in and made of with some 20,000 artifacts, representing the greatest and most grievous such robbery in history. To date, only some 5% of those artifacts have been recovered.