Very recently some new projects using RubyCocoa were released to the public.

TimeToTicket, a tool to report your working hours in the RedMine project management system.

CocoaNav, an application to elegantly browse frameworks and classes. Very cool animations.

osx_trash, a command-line tool to easily manipulate the Mac OS X Finder's trash.

And, it's hard to not mention GitNub, a desktop frontend to the git source control management system. This isn't really a new project, but it's starting to be popular in the development community.

This really demonstrates that RubyCocoa is being adopted by more people, and more importantly, Ruby as a language to write Mac OS X applications. And the future is not that far now!