I was waiting exactly this kind of plugin for a while !! (directory wp plugins already exist but they are not very cool. I hope Malaiac will give us Zeplugin and will be able to make it happen with time) !
Zelist works only with WordPress 2.7 and higher but Hey nice, WordPress 2.7 beta 1 just released.
I will wait for next versions because I don’t like so much alpha-beta versions…
To see the tool working, go to Zelist demo (french).
Nice add-on : you can also import an existing Freeglobes directory in Zelist.
I would love a Paypal integration and automatic tool to check reciprocal links. Would be nice in the Future.