The DynatOS Project is an OS dev project going on for over 5 years now. I've been slow to do major work on it (work/school/obligations), but it is as much for my leisure as it is for learning and actually releasing it some day.
I started OS Dev by going the infamous "fancy bootloader" route, but arrested that mentality quite some time ago. This included taking some useful code out of the kernel source such as CLI routines and simplistic drivers, but that will be added on again to the "OS" part of the OS (not the kernel).
So far, The Core (kernel) loosely follows an exokernel-style design, and is written entirely in x86 ASM (i386 to be precise) using NASM. The rest of the "OS" will most likely be written in more portable langauge (C).
If anyone is interested in joining the project, feel free to contact me. I am willing to work with whomever is interested to achieve this exokernel-style objective... though the project name "DynatOS" (Greek for "Powerful") is non-negotiable