Yep, this is possible. In fact it's what I use; for good or for bad, I leave my MBR under Window's control..
This seems to work with many flavours of Linux - Debian, Ubuntu, Mepis, Mandrake are just a few I have checked out.
The basis is outlined here: http://www.geocities.com/epark/linux...2k-HOWTO.html.
It's designed for Redhat, but seems to work for any linux, with minor tweaking. Perhaps I'll write an Ubuntu specific version.