Have an idea for small computer, need info...

I need some info on PC/104 or similiar small board. I don't need top of the line stuff, something in the range of 500MHz P3/AMD should be enough. If I ever get the money and the motivation I'd like to try and build a very discreet PC inside the book (see below) as I have that sitting around unused. I'd probably use wireless keyboard and mouse so all it'd have sticking out are power cable and monitor cable.

And use a giant capacity flash drive or Microdrive as bootable drive. Isn't Microdrive some type of IDE or maybe I was in error? I know Microdrive is slow but they aren't limited by number of rewrites like flash ROM.

Would PC/104 do it or am I looking at something else?

There are adapters that allow you to connect a microdrive to an IDE cable and boot from it.

If i were you i'd pick up an old laptop and use parts of it, any desktop / atx stuff is way too large.