Creole

Creole is an Eclipse plug-in that brings Shrimp dependency visualization to Eclipse/Java.

Hudson

Hudson is a Java-based continuous build server that requires much less configuration than CruiseControl.

VisualVM

VisualVM 1.1.1 is starting to show some nice, practical functionality.

Terracotta

Terracotta is a Java-based system for sharing objects across VMs -- "network-attached memory".