A few funny Seinfeld-movie connections I've noticed:
An entire episode of Seinfeld revolved around how bad "The English Patient" supposedly was. The director of that movie, Anthony Minghella, followed it up with "The Talented Mr. Ripley", which included performances by two actors who've been on Seinfeld, Philip Baker Hall (Joe Bookman), and Jack Davenport (the prosecutor from the finale). I wonder if he realized two of his actors had been on a show that had destroyed his previous movie!
Also, Bob Balaban (Dalrimple) had a small part in "Midnight Cowboy", another movie Seinfeld has made reference to ("The Mom and Pop Store"). If I remember correctly, he plays a gay man who makes sexual advances toward the Jon Voigt character in a public bathroom.
Some more obvious examples of Seinfeld referring to movies that its actors have been in are Wayne Knight (Newman) in the JFK parody, and Marisa Tomei ("My Cousin Vinny").
Any other examples?
�mile