I could be wrong, but this is probably the only JRUBY + JXTA screencast out there. Perhaps the only JXTA screencast?
Using Wink, a free screen capture tool for Linux or Windows, I threw together a quick demo of where I'm headed in terms of of developing a JRuby abstraction layer of insulating developers from the gory details of JXTA. Nothing fancy, I basically set some environment variables, fire up jirb and create a new JXTA peergroup in about two lines of ruby.
And the best thing is you don't get to hear my grumpy, allergy-laden voice!