The folks at SapphireSteel Software have released a new version of Ruby In Steel, called Text Edition, that doesn't require you to already have a Visual Studio license, and it's only $49 at this time!
For those who don't know about it, Ruby In Steel is a full Ruby and Rails development platform for Windows with real time debugging (breakpoints, mousing over and typing variables to see their values), syntax error detection, color coding, indenting, and anything else that you'd want in a full featured IDE. Check my previous blog entry, Ruby In Steel, Ruby on Rails add on for Visual Studio, for a better description. Previously, Ruby In Steel was an add on for Microsoft Visual Studio, you already had to have a Visual Studio license for this to work.
This new version comes with a free version of Visual Studio 2008 that it uses behind the scenes, but you can only do Ruby and Rails development with it. They still sell the Visual Studio add on. The main differences are that the add on version has a faster debugger, and uses the Intellisense libraries that show possible values for objects and attempts to highlight incorrect syntax. If you already have Visual Studio, I'd still recommend the regular version, but if the price is too much the Text edition will still work great. The Intellisense in the full version still doesn't work too well with Rails code (but what can you expect since it's not strongly typed), but it does work pretty well for strict Ruby code. But if you don't have Visual Studio, the Text edition provides a very powerful full featured Ruby and Rails IDE for a great price, I would highly recommend it! You can get it at http://www.sapphiresteel.com/.