Similar to the Computers page, but instead for microcontrollers. They're usually ARM, MIPS, or RISC based, although not always. Some will be m68k or PPC based, and there will be many other obscure architectures found in this field. Operating systems will be even more varied, and cannot easily be generalized.

uses the CTK VNC server instead of a regular screen.

Unlike Linux, this is running natively on the ATMega chip. Capable of interfacing with Ethernut hardware and prefers remote screen (VNC) over any other display output.

http://hitmen.c02.at/html/tools_contiki.html

https://github.com/contiki-os/contiki/tree/master/platform/avr-atmega128rfa1

boots Linux 2.6.34. It can even bring up a full Ubuntu, including (if you have the time) X/Gnome

An astonishing feat, done by emulating an ARM chip on this tiny little 8-bit chip. This conceivably could be done on any 8-bits. It does not even require a printed circuit board. Furthermore, upon booting (which takes ages), the system is actually quite usable!

https://www.youtube.com/watch?v=nm0POwEtiqE

https://dmitry.gr/?r=05.Projects&proj=07.%20Linux%20on%208bit

a 1GB or greater microSD card

A manufacturer-provided demonstration of putting the Linux kernel on these little chips. The manufacturer also sells SD cards that already have a bootable Linux image.

https://www.acmesystems.it/aria (Chip info)

https://www.acmesystems.it/pricelist?category=aria (Purchase here)

https://www.acmesystems.it/ariag25_compile_linux_2_6_39

This is just a writeup outlining the technical characteristics of a Linux 2.6.33 port to a hypothetical Cortex microcontroller. Good for reference.

https://elinux.org/images/c/ca/Spreading.pdf