There was a tidbit couched in the recent announcement about Groovy 1.5: there is a joint compiler that eases the compilation of projects that use both Groovy and Java.
I want to highlight that JetBrains contributed it.
I have no affiliation with the company. I simply think that is very cool and a savvy business move with respect to goodwill.
From the Open Musings Department:
As I write this, I was about to joke that the joint compiler code might have an advertisement in the comments:
// "Brought to you by JetBrains, makers of Idea"
Maybe that's an idea? Hockey rinks, race cars, and baseball parks are plastered with ads: what if open-source projects allowed (regulated) ads in (a) the comments or (b) the startup console. Would that encourage contributions? Would it cause political issues? Hmmm.....