The Robot Co-op, the team behind 43things, has released several great Ruby libraries for free, all available as gems. Here are some of the highlights:

AD.D SoftWare have developed a new plugin for Rails called cssForm that lets you create forms without tables, entirely using CSS.

There are a few efforts to develop crossovers between .Net and Ruby, but Ruby.NET one that is creating a compiler for the Ruby language that targets the .NET CLR in much the same way as JRuby targets the Java Virtual Machine. This particular implementation is unique in that it can pass all 871 tests in the samples/test.rb of Ruby 1.8.2.

The unstoppable Coda Hale presents an amazing article about setting up a server with Mongrel, Apache, Capistrano, SSL support, etc. for solidly serving Rails applications. An extremely well written and solid guide.

Tim Hunter, of RMagick, the Ruby Image/GraphicsMagick library, has put together a cool tutorial about how to use RMagick to produce Web 2.0 style graphics, as shown above. It's pretty in-depth.

If you want to cut down on the nastier elements getting through to your Web site, filling in contact forms, and generally causing havoc, consider the rbl_check plugin by Joost.

RubyNode is an interesting Ruby library that spits out semantic representations of code much in the same way the inspect method does with data. Here's a demo:

mly from caboo.se looks at how to quickly protect certain controller actions from GET requests in Rails, and presents a couple of useful test helpers to make testing for POST vs GET compliance simple. His code lets you then do a simple test like so:

Many coders will reach a situation where developing a C extension makes sense, whether for doing 'heavy lifting', diving into assembly language, interfacing with other C code, etc. Luckily, developing a basic Ruby extension in C is easy.

Above: Courtenay's team hard at work.