I'm involved in different OpenSource Projects because of many reasons. First of all I'm working for Red Hat which is a OpenSource Company. So I'm lucky enough to work on them as part of my job. But not all are related to them, as most of all it is my passion.
This page tries to list all of them:
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients.
Vert.x is a lightweight, high performance application platform for the JVM that's designed for modern mobile, web, and enterprise applications.
Maven plugin that runs tests of the (Autobahn Testsuite)[http://autobahn.ws/testsuite/] as part of your build
The jSPF library is pure Java SPF implementation. It was designed to match the current SPF-Specs of 2006-2009 (See RFC section). SPF is also knows as Sender Policy Framework. It was designed to detect email spoofing.This is the solution if you ever was tired of getting spam from yourself.
A NIO implementation of a SMTP/LMTP Transport and Agent