Sparko the Electronic Dog has a faux cameo in Batman: Mask of the Phantasm (1993)!
Referred to as "Rusty" by the Joker in this scene. Additional info and reasoning:
This is one I'd noticed before but wasn't as confident in, until @Strangled-Mangoes also noticed it independently and sent it to me for review--which made me reconsider my initial skepticism and realize he was probably right (thanks for the submission)! As noted on this blog previously, Batman: Mask of the Phantasm takes heavy inspiration from real world's fairs for it's main setting, the World of the Future Fair. In particular, the 1939 New York World's Fair and the 1964 New York World's Fair (see that linked post up there for more on that). The exhibit Rusty is found in itself--known as "House of the Future" in the movie--appears to be inspired by the real world Carousel of Progress exhibit from the 1964 New York World Fair (which has since been adapted into an attraction at Disneyland in Anaheim, California), depicting various decades of U.S. household living with a focus on changes in technology. This is seen most obviously through this animatronic woman in the movie mirroring the appearance of this extremely similar one in the first stage of the Carousel of progress, but also through the general theming, setup, music, and, of course, the inclusion of an animatronic dog.
The real animatronic dogs (plural--there were multiple playing one character, Rover, across different scenes) of the Carousel of Progress are tremendously fluffy, grey and white, and have semi-realistic features and proportioning. Here's a photo from the 1964 edition of the exhibit, and a modern Rover from the Disneyland attraction.
Sparko the Electronic Dog--while instead being from the 1939 World Fair rather than the 1964 one and having no relation to the Carousel of Progress--resembles the one seen in the movie far more closely. Extremely closely. The color, body shape, tiny eyes, jointless "stick-limbs", straight (though damaged) pointy ears and tail all feel very directly inspired, especially given how closely the other animatronic we see sticks to its original real-world counterpart's appearance. That, combined with the other 1939 World's Fair inspiration seen in the movie (again, see that linked post up there for an Elektro sighting--Sparko's more famous buddy). This is probably the most dead-on (faux) Sparko cameo we will ever see.











