Hi again Stephen...
That's actually the same plug-in I've been working on... The newest version (2.9.8.2) doesn't work at all but the last working version for WP 2.9.2 was wp-recaptcha 2.9.6.
I've had to do some altering but at least now I can install the plug-in and it will save the configuration without throwing an error or telling me in the plug-in section of WP that I have to enter the public and private keys...
Now all I have to do is figure out why it won't show up on the comment form... After installation and configuration are done, there is no evidence (either with rendered html or java) that the plug-in is working at all...
I know I'm probably just missing something simple.
On another note... There are directions on how to install the plug-in for Wordpress MU but if they are followed it takes down the entire blog (white screen).
I'm happy to attach my work so far if someone wants to take a crack at it...

Again, if I solve the riddle, I'm happy to hand it over so you guys can offer it in the plug-in area.