A smartwatch with the capability to record videos and play them back. How else are you gonna be a sci-fi kid making your video journal or stranded miner on the Deimos refinery? This could be done with current smartwatch technology (even the cheap Chinese ones), except maybe for the lower quality screens. One hurdle would be a good battery life and still be thin enough for practical use
I backed the indiegogo for the Lichee Pi Zero, and hopefully it will be arriving in the next month or so. If you haven't heard about it, it's basically an SD card sized, breadboardable Pi Zero clone. Here's some links: