I've noticed some interest in somthing like this, but still can't find one.
For anyone technical I'm sure it would just be a matter of finding an existing script can converting it to a plugin.
e.g. I'm planning on using this one: http://www.phpjunkyard.com/php-link-manager.php ... but of course will need to do a lot of fiddling to get it to fit in with my blog/design etc
Any god-like heros out there? :)