I have listened the general session (supervised by James Gosling) about various innovative robotic-oriented products, like helicopters, submarines, industrial robots etc. One special - the WowWee robosapien V2 - was presented as well. Now I have one too! :)
The session called Bytecode Manipulation Techniques for Dynamic Applications for JVM was really good. First, Eugene Kuleshov described ASM quickly, and after that some of the applications were descried: TopLink, Terracota DSO, and JRuby language compiler.
Next, I attended Java Puzzlers session, brought by Joshua Bloch & William Pugh.
Finally I was at JRuby session about DSLs. I didn't really get the point here actually. What's the point of implementing a specialized language for a corporate actions calculations? We can do the same Java and support it even better, specially if we have high performance requirements, which is not applicable to JRuby at the moment.