The cheapest single-board computer is one you probably already own.

Google and Raspberry Pi has teamed up to bring voice commands and artificial intelligence to the maker community. As such you can now get the Voice Kit, a low-end Android Assistant box that you build.

Thanks to its Linux roots, Android can be installed on almost anything that has a processor and enough space for the software. Beyond the usual culprits, you also have TVs, dashboards, and even the ...