The Millennium Falcon from the Star Wars saga makes a cameo appearance in this movie. Take a close look at the exterior shot of the Space Diner, and it can be spotted parked there among the other space vehicles. George Lucas got a chance to read the screenplay before production began, and loved it so much that he decided to have his special effects company, Industrial Light & Magic, help make this movie.
In a 2013 television interview (shortly before receiving the AFI Lifetime Achievement Award), Mel Brooks stated that he personally obtained George Lucas' full permission to parody any and all things Star Wars-related but, on one condition, that absolutely no merchandise of any kind be produced from this movie. This is the reason why all Yogurt and the Dinks do is merchandising (it is also why none of the merchandise seen in this movie was ever mass produced or publicly sold in any way).
Mel Brooks asked if Daphne Zuniga wanted someone else to sing the bit where Vespa is in the cell singing "Nobody Knows the Trouble I've Seen," but she insisted she could do it and she was right.
The scene in which Dark Helmet is playing with his dolls was not in the screenplay. Writer, producer, and director Mel Brooks came up with the idea on the set one day and told this to Rick Moranis, who then improvised the entire scene.
In the DVD audio commentary, writer, producer, and director Mel Brooks speaks about how difficult it was playing the character Yogurt. The gold-colored make-up gave him a terrible rash on his face and neck (necessitating the shooting of most of Yogurt's scenes out of sequence), and, since he had to walk around on his knees, they were hurting constantly even though he was wearing kneepads. Brooks also goes on to say that in spite of the difficulties, he enjoyed playing Yogurt tremendously, and that it was all worth it.
Mel Brooks: [cast] Mel Brooks cast himself as President Skroob and Yogurt, and cast Dom DeLuise as the voice of Pizza the Hutt.