I am a Java/J2EE developer with about 5 years of work ex and with plenty of free time

I've been like this for a over now. I even switched jobs but I remain under utilized no matter where I go

I am volunteering for open source projects and am ready to give my 5 cents in Java/J2EE projects where I can help.
Any pointers to places to start for open source projects would be of great help as well!