JavaWeather is multithreaded Java code which connects to the NWS servers to download current weather conditions and forecasts from 3,000 observation stations around the US and the world, and provide bean-like access info for Java applications and servlets (not applets). It also includes some temperature utilities.
JavaGroups is a Java package for reliable group communication. It consists of 3 parts: The first part is a socket-like API for application development, providing methods for joining and leaving a group, sending multicast messages to members, and receiving notifications when members join/leave/crash. The second part is a protocol stack which implements reliable communication, and can be configured according to the QoS desired. New protocols can easily be added, and existing ones removed/replaced/modified. The third part is a set of building blocks which give the application/protocol programmer high-level abstractions (e.g. DistributedHashtable, derived from java.util.Hashtable, which is similar to Linda/JavaSpaces).
JBidwatcher is a powerful eBay-user tool implemented in Java. Its features include tracking of auctions, bidding, sniping (automated bidding in the last moments of an auction), and a unique multisniping feature that allows you to snipe on a group of auctions, but stop the sniping as soon as you win one. It also includes remote Web-based management, XML-formatted save files, drag and drop support, some support for auction sellers, and dozens of other useful auction features.
JBoss is an Open Source, standards-compliant, Enterprise JavaBeans application server implemented in pure Java. JBoss provides JBossServer, the basic EJB container and JMX infrastructure, JBossMQ for JMS messaging, JBossMail for mail, JBossTX for JTA/JTS transactions, JBossSX for JAAS based security, JBossCX for JCA connectivity, and JBossCMP for CMP persistence. It integrates with Tomcat Servlet/JSP container and Jetty Web server/servlet container, and enables you to mix and match these components through JMX by replacing any component you wish with a JMX-compliant implementation for the same APIs. The goal is to provide a full J2EE stack in the Free/Open Source software world.