This post is more than 2 years old.
Earlier today I wrote up some thought I've had recently on writing ColdFusion Administrator extensions. You can find the guide here. It basically covers what the docs talk about but also details some tips and tricks that developers may want to know about. I also listed all the known CF Admin extensions and hope that people can suggest a few I forgot.
So I know like a grand total of 4 or 5 people actually write these things, but maybe this will encourage others to create their own.