JGroups - A Toolkit for Reliable Messaging

Shows 2 instances of Draw and a graceful leave, plus a crash-leave. The flash demo can be found here.
The Java Webstart demo can be found here (start multiple instances).

Note that you need a resolution of at least 1200x1024 to view the flash presentations !

Shows 2 instances of Draw which share a common state. The state is the canvas onto which we draw.
The flash demo can be found here.

Shows 2 instances of Whiteboard. Whiteboard is a simple presence application, showing each cluster node with a box with the user's name and information about the operating system and JGroups address.
There's also a simple chatting functionality, where messages can be sent to individual nodes, or to all nodes in the cluster.
The flash demo can be found here.

Here we show 2 clustered stock servers, which replicate data between themselves. Any update (addition, modification or removal) is replicated between the servers.
We also show how a new server acquires the stocks from an existing member (state transfer) and how a server can be restarted without the cluster losing its shared state.
The flash demo can be found here.

Here we show how to run the Draw demo with different stacks. The first example is UDP, then we look at the different protocols and then use TCP.
The flash demo can be found here.

This demo shows 4 instances of ReplCache forming a cluster (cloud storage). The demo can be downloaded from http://downloads.sourceforge.net/javagroups/replcachedemo.jar
The flash demo can be found here.
The Java Webstart demo can be found here (start multiple instances).