Doug,

>>Having a client who has products based on the PPC 405 and 750, I am
>>definitely in expanding into systems which run on these processors.
>>Unfortunately, their systems are very expensive, and so I am limited
>>to working remotely on systems in their lab.  However, I have been
>>looking for an inexpensive implementation such as the Walnut EVB, with
>>no success.  Your mention of being able to get a board makes me want
>>to know more.

I am not entirely sure what you are looking for in a system, but a while 
back I worked on a couple different borads with 405 processors. Both ran 
NetBSD wonderfully, although the CerfCube required a few kernel tweaks to 
accomodate its 405EP processor (as opposed to the GP). Both are good systems 
to prototype stuff on - and very reasonably priced.

CSB472 (IBM405GP), by Cogent
http://www.cogcomp.com/csb_csb472.htm

CerfCube 405EP (IBM405EP), by Intrinsyc 
http://www.intrinsyc.com/products/mob_ref_sys/cerfcube_405_ep/index.asp

Best regards,
Jared Momose