Bran's Kernel tutorial

A very interesting ressource can be found at: http://www.osdever.net , it's called the Bran's Kernel tutorial, and it aims to give you a step by step introduction into writing your own operating system kernel, it starts pretty much from the very beginning and walks you through the major steps of designing a DIY kernel from scratch.
I have myself followed the first steps of the tutorial (still going), i found a few errors in the provided code, when i corrected them it compiled with no problem, then i assembled the startup routine (in assembly) and linked everything in one single file called kernel.bin, wich should be the executable image file of my kernel, however this image file has not been recognised as a valid kernel by the Grub boot loader, it must be a configuration problem with Grub, i will try to fix this up soon, if it doesn't work i will send an e-mail to the author, ...
I strongly recommend this website as a reference for anyone who wants to get started with custom kernel development.
If you are particularly interested in the Linux kernel or if you want to take it as a guide line, there is also a generic collection of ressources that can help you, here's the link: http://jungla.dit.upm.es/~jmseyas/linux/kernel/hackers-docs.html
have fun.