HotCocoa!

The latest MacRuby with HotCocoa is amazing! Finally a way to write OS X applications without having to learn Objective-C.

require 'rubygems'
require 'hotcocoa'
include HotCocoa
application do |app|
  win = window :size => [100,50]
  b = button :title => 'Hello'
  b.on_action { puts 'World!' }
  win << b
end