You can use the NetBSD drivers for other operating systems pretty easily - see http://rumpkernel.org/ - you can get filesystems, IP stack, network card drivers, etc. Several new OSs are using them.

Thanks, that site was really interesting! I hadn't heard of rump kernels before.

I have no idea. I discovered this researching secure OS work such as Flask. It does have plenty of documentation [1]. Maybe that will help you.

[1] http://www.cs.utah.edu/flux/oskit/html/oskit-www.html