In the Seinfelds' condo board newspaper, Boca Breeze, the name Larry David (famed head writer & co-creator of "Seinfeld") is found in three successive smaller headlines: "Larry David gets hole in one!", "Larry David Hurts Elbow" and "Larry David Never To Play Golf AGAIN".
George's (Jason Alexander) line, "You wanna' get nuts? Come on! Let's get nuts!" is what Bruce Wayne (Michael Keaton) says in Batman (1989).
The hot dog vendor George (Jason Alexander) is talking to near the beginning of the episode is played by Michael McShane, who also played Kramer's (Michael Richards) enemy Franklin Delano Romanowski aka FDR, who wants him to drop dead, in The Betrayal (1997). FDR was also a hot dog vendor so it's likely the same character.
First credited role for Samuel Bliss Cooper (Elaine's boyfriend, "Daryl").
Bob Sacamano is a fictional friend of Kramer (Michael Richards). He is never seen but is the source of many bizarre anecdotes. Larry Charles has stated that Sacamano was a real-life friend, although the two fell out shortly after the character was first introduced. Throughout the course of the series he was referenced in the following episodes: