Building an AMD 64-bit Linux system

I've finally decided to build myself a new computer. The last time I built one for myself, I attempted to be fairly conservative, and stick to known configurations. This time, I decided to throw caution to the wind and build something a little closer to 'bleeding-edge'. Since the system would be designed to run Linux (Mandrake-Linux specifically), basing it around the AMD Athlon 64 was a farily obvious choice - there was a current Mandrake version for AMD64, AMD appears to be actively supporting Linux and, just to show that we all fall into lockstep behind him, Linus has been quoted as believing AMD64 to be the better technology :)