For those with an interest in LegoMindstorms?, or ExtremeLego, see sourceforge.net/projects/lejos/
Synopsis: A project named leJOS was started to challenge and inspire programmers to create a Java[tm] virtual machine (JVM[tm]) for the RCX, which would enable people to program their robots in the Java programming language. The creators of leJOS have managed to squeeze a lot of Java technology functionality (including multi-threading) into only 17 kilobytes of code.
ExtremeLegoMindstorms