A few things.

A laptop with 2-way HDMI, so i can plug it into a game console and use it as a small TV. Note that i’m aware that HDMI might not work like this.

A wearable soundboard with speakers and batteries hidden in my pockets, and controlled by chorded buttons in my shoes. Use cases include crickets, canned laughter, the Seinfeld theme, and audible air guitar riffs.

A handheld computer that:

• Has physical buttons instead of a touchscreen
• E-ink display for all the benefits of that – Physical light switch for a backlight for the screen (my phone is e-ink but i have the backlight turned off by default, a side effect is i can’t see the screen to turn the backlight on when i need it) – Button to refresh the screen, instead of relying on automatic refreshes (Light Phone II) or updating what’s on screen to get it to refresh (Sony PRS 505) – Solar panel, if the OS is light enough to permit it. Ereaders are totally low-power enough that if one had a small solar panel like a calculator you’d almost never need to charge it. A full handheld computer could probably also benefit from this.

A music player / DAC that:

• Has physical buttons, non-touch screen, & light switch for screen backlight like the above wish.
• Lets you mark some files as audiobooks/podcasts, so it remembers your place in those
• Isn’t just an Android phone that can’t make calls
• Has a reflective or transflective display, so you can use it outdoors without fighting the sun
• Can listen to the radio, if you unfold or plug in an antenna
• Has a headphone jack There’s more to this one because i’m planning to actually make it someday, simply because i don’t expect anyone else to make one that does what i want it to.

Somewhat ergonomic keyboards in laptops. I know split keyboards are hard because the screen has to be about as wide as the keyboard, but i’m sure there’s a way and i intend to someday prove it. I know we can do better than typewriter shaped keyboards with QWERTY by default, even ortholinear boards would be an improvement because layouts can be done in software.

An electric notebook with a touchscreen that instead of using OCR to turn handwriting into text, stores handwriting as vector graphics as a middle ground between OCR and images with huge file sizes. Probably with a slider for how much to simplify lines, and an option to select areas of a page to convert to text via OCR so you can still have diagrams and doodles alongside plain text that’s easy to export and edit.

A device like a generation I pokedex, but for real world animals and plants. This one probably won’t happen because stuff like this is only done as smartphone apps anymore, not as standalone toys.

HUD goggles that are the display of a full portable computer.

• Keyboard input could be done through a split keyboard that hooks onto your belt, with half on each thigh
• Mouse input could be done with a trackpoint / trackball on the keyboard (simple option) or with a bracelet that emits IR light from multiple points so it can be tracked by sensors on the goggles (if you don’t understand what i mean, kind of like a Wiimote and sensor bar), with a ring that goes around your middle finger attached by a wire to the bracelet. When you tug the ring down by bending your wrist or fingers down, that’s a mouse click. (complicated option)
• Two or more hot-swappable batteries, so you can change one out without the device having to lose power
• Transparent LCD over one eye, so the background of the image is just what’s actually in front of you
• Gyroscope somewhere on the head part, so you can turn your head to access different windows like it’s a VR headset. Imagine there’s a bubble around your head with program windows projected onto different parts of it. Large windows look curved around the surface of the bubble. You can drag them around with the mouse, or turn your head to move them relative to your eyes. Probably also makes this good for AR stuff.
• Headphone jack and bluetooth for audio, but not necessarily built in speakers This one might never happen, apparently making any kind of HUD is very hard and expensive and this one is asking for a lot. But it would be so cool. It would finally be a portable computer with a good input system (keyboard) and a display at the same time.

And there’s more stuff i want to exist that doesn’t fit the question. Software (why hasn’t anyone mad a 3+ D spreadsheet program?) and non-technical products.