best way to configure a machine for kernel development

[Aryeh M. Friedman]

I decided to put my fingers where my mouth is and jump into kernel
development instead of just complaining.   Configuring a machine
properly to do this most effectivally I guess is the next step.   I only
have one machine (I have some modest but non-critical production stuff
that needs to continue working).   Some options I have come up with:

1. Just hack my current sources and keep diffs (some automated way would
be nice of edit-->make diff)

2. Use QEMU to create a development machine

3. Someone said something about unionfs and/or using a cvs mirror but I
missed that completely missed that

Any other suggestions.   Also since I tend to be a little slow on the
learning curve can you also point me to some good howto/tutorials on
what ever solution you suggest?

-- 
Aryeh M. Friedman
Developer, not business, friendly
http://www.flosoft-systems.com