Unrelated to Apache Click, but still some interesting and very useful open source projects created by the Click Community.

1. Mirage

A small and efficient DB access library for projects where an ORM would be an overkill (it's also an efficient alternative to DbUtils).
There's also a small example web application with Mirage and Click.

2. AmaterasUML

Eclipse UML plug-in, with support for Class, Sequence, Activity and Use Case Diagrams, with a very interesting API that allows scripting and generating of diagrams from code (see the Scripting API section).

3. AmaterasERD

Eclipse plug-in for simple and quick ERD modeling of databases.