Joachim reports on a cool Apache module for Seaside apps (Pharo only at the moment):
How does this actually work? There are two Apache modules involved. mod_advertise sends UDP broadcasts about Apache's location, you might have several on different hosts in the network. mod_cluster_manager allows remote configuration of Apache. Seaside will connect to the advertised Apache instances and tell them where it is (host, port, protocol, urls).
Joachim has an overview of what's been done; the listserv posting by Phillippe Marschall has far more details. Very cool stuff. Setting up a simple round robin load balancer with session affinity has been possible for Smalltalk aps for quite some time, of course - this just goes up to the next level.