Looking for open-source Java projects to participate

Question

Java

Looking for interesting Java projects to participate in the development.

Interested in the web or part of the desktop, not related to mathematics and graphics.
I have some production experience, I know Core Java with confidence, I’m quite familiar with patterns, ORM, I know many common libs and frameworks at the “you can start working” level, I know GWT well.

Answer 1

Look here: sourceforge.net/
There is a search and rubricator for programming languages.

Answer 2

You may be interested in jtalks.org - the link contains a description of the project.

Answer 3

Here is about my project: http://habrahabr.ru/qa/11399/ . Maybe interested.