* '''DevLib''' - Homebrew library for embedded development that includes a small multitasking kernel. * '''uClinux''' - A Linux kernel and distribution targeting several MMU-less microcontrollers. * '''Nut/OS''' - Nice OpenSource RTOS for 8/16/32bit systems. See http://www.ethernut.de/en/software.html . * '''FreeRTOS''' - Yet another OpenSource RTOS. See http://www.freertos.org/ . * '''QNX''' - A microkernel RTOS with a wonderful system architecture. * '''AmigaOS''' - Almost an embedded OS, and definitely an RTOS.