>Take a look at the ts7200 machines, with support in the evbarm port.
>I suspect they might be just what you need.
>
>http://www.embeddedarm.com/epc/ts7200-spec-h.html

Hmmmmm .... considering this is close to the cost of a Soekris box (which
I was planning on buying anyway), this might be the leading contender so
far.  The only wrinkle is that I'll probably have to write a device driver
for the A/D module, but that probably won't be too bad.

Thanks for all of the suggestions; I had no idea there were so many
options!

--Ken