...you might like to take a look at a few screenshots showing the IronRuby form designer (alpha) which my company (SapphireSteel Software) is working on. IronRuby is the name of Microsoft’s version of the Ruby language for .NET. It’s still in any early stage of development and our form designer will necessarily change as IronRuby itself develops.
Still, it’s a first step towards a truly RAD Ruby IDE. As an old Delphi programmer, that is something I long for...
More info: http://www.sapphiresteel.com/IronRuby-Visual-Form-Designer