Tinkering with Linux on mobile devices quite a bit, the growing pile of Linux tablets and phones on my desk often looks underutilized. I wish I could wire some of those lonely black slabs together and extend my monitor, or why not, use them as controllers for my desktop windows in a half PARC Tab, half Stream Deck fashion [0].
Yet if any reasoning adult will know that USB-C looking symmetric does not imply it is also very useful to transfer things between peer devices, I still think that using my tablet as a secondary screen through Wi-Fi would be a lifesaver e.