On Jan 10, 2005, at 5:45 AM, Thomas Counsell wrote:

> If you want something that will allow you to develop native Mac OS X 
> guis, then you can use Mac's XCode together with rubycocoa 
> (http://www.fobj.com/rubycocoa/) to draw them.

You aren't limited to Interface Builder. You can use XCode to edit ruby 
source complete with syntax coloring, class/function popup, and 
multiple files in the project.