When Richie says "Sounds like a Bunuel film" he is referring to Luis Bunuel, a Spanish avant-garde filmmaker active from the 1920s - 1970s.
When Seth enters the Big Kahuna Burger the waitress says "Aloha, Welcome to the Big Kahuna Burger, would you like to try our Special Agent Utah meal?"
Keanu Reeves was Special Agent Johnny Utah in Point Break which also starred Gary Busey. Jake Busey plays Professor Aiden Tanner in this episode.
When Seth calls his guns Thing 1 & Thing 2 he is referring to characters from the Dr. Seuss book 'The Cat in the Hat'.