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The San Francisco streetcar that Dr. Cockroach, Ph.D. modifies with rocket engines is an Italian-made vintage Peter Witt streetcar in the 1928 white-and-yellow color scheme. The streetcar in the movie has number #2930 (as of release, not an assigned number).
The monsters shown in the movie are all references to original monsters in movies. Ginormica is a reference to Attack of the 50 Foot Woman (1958), B.O.B. is a reference to The Blob (1958), The Missing Link is a reference to Creature from the Black Lagoon (1954), Dr. Cockroach Ph.D. is a reference to The Fly (1958), and Insectosaurus is a reference to Mothra from Mosura (1961).
For the scenes of Ginormica wandering the streets of San Francisco, a replica of the set was built, and supervising animator Line Korsgaard Andersen was videotaped walking around it as reference for the animators.
When Gallaxhar is talking to Earth about what he is about to do, when he is talking in Tokyo, Japan, on the top left corner, a scene from Madagascar (2005) can be seen of Marty talking to Alex.
The first computer-animated movie directly produced in a stereoscopic 3-D format, instead of being converted into 3-D after completion.
In the Australian release, David Koch voices the News Reporter. Koch is co-presenter of "Sunrise", a morning show shown on Channel 7 across Australia.