What's in the Chest

Zoe and Dirk sat in the bright as day basement room that now contained everything left in the world from their dad. He had passed after being involved in one of the now rare deadly car accidents that still occassionally occurred even with computers taking the slow response times of humans out of the equation. He had warned them both that he was most likely going to end up dying that way while they were still young, but it still surprised them when it actually happened.
They had been going through bins, books, boxes and clothing and so far had spent most of the weekend sorting through and dividing up this or that based on their memories and tastes.
Dirk had most of the clothes.
Zoe had most of the books.
They had found old corny dad jokes everywhere and couldn't help but laugh each time he tricked them into saying something funny or made them remember the first time they had reused his corny old jokes with their friends. He couldn't help himself, it was just the way he thought.
The last thing to be sorted, was Dads old chest. It weighed over a hundred pounds and if it didn't have those caster wheels, would have been unmovable by them. It was half pink and half blue with both of their names embossed on the side that corresponded to their favorite colors indicating that this was for both of them to share.
"I bet it is another one of his jokes," Dirk says whistfully as they open the lid and peer inside.
Inside were two compartments with identical looking cases other than the coloring and embossing matching the chest indicating which belonged to who.
Zoe opened her case first and had to step back as it flipped end over end and began inflating like one of those lifeboats only this didn't turn into a big orange seagoing vessel, it somehow became big pink colored round looking saucer ship thing with a clear dome cover.
"No way!" A Jetsons CAR!" Dirk yelled behind her apparently recognizing the gifts.
"How the hell did Dad cram these things inside those cases?" Zoe said outloud.
"He was doing tons of research on carbon nanotube contruction with his AI over the past few years." Dirk responded apparently more in touch with Dad than Zoe had been lately.
Zoe reached out and grabbed the obvious handle that still looked like it was the handle on the original case and the car began its chaotic changing in reverse ending up spewing air around itself in a clear immitation of a fart as it squeezed the remaining air out and finally regained the case form once more.
Both laughed their asses off until they cried as they realized that their Dad had left them with something that would probably make them laugh every time they used it, but was still so awesome that they couldn't help but use it anyway.
"Thank you Dad." They found themselves saying in unison even though he was not there to hear them.