I'm a computer security specialist and I plan to implement a software to deal with security policies, all using Cocoon.
A security policy is made of multiple rules, each rule having specific fields: that fits well into a database, and the fields are easily rendered into XML, thus into whatever else I could imagine (XHTML for on screen display as well as PDF for pretty printed security policy). Add searching to this, keyword lookup, etc.
I've been looking at Cocoon since quite a while, now, but it's time to get my feet wet. Not really easy, though