I don’t think it’s possible for aftermarket car fobs to be a thing, but if they were I’d like to see one based on the Communo Crystal device from the Last Starfighter. I doubt Centauri would come to the rescue if the Alarm button were pressed.
Cars
Arrested Development Bluth-Ray Case
UPDATE: originally I had a fancier design where they discs would jack-knife out of the stairs but I grew to hate the idea. Discs shouldn’t be so hard to access. So I turned the truck into a napkin holder for normal blu-ray cases.
Dark Knight Trilogy Blu-Ray Case
Here is blu-ray case design for Christopher Nolan’s Dark Knight Trilogy. Three CD-sized jewel cases are enclosed inside the Tumbler, which opens in similar fashion to the real-life Batmobile. This case would be on the larger side, about 12 inches long and 5 inches tall.