"CukeSalad is a Cucumber extension that allows you to focus on the task at hand - expressing examples, the roles involved in those examples and what those roles can do with the product under development."

"rQRCode is a library for encoding QRCodes in Ruby. It has a simple interface with all the standard qrcode options. It was adapted from the Javascript library by Kazuhiko Arase."

"It is my opinion, that anybody should be able to use Couch in Rails or Sinatra or plain Ruby application as easily as using ActiveRecord, or, maybe more importantly, the highly faved MongoDB. Please share your opinion in the comments."

"BayesMotel is a multi-variate Bayesian classification engine. There are two steps to Bayesian classification:

Training You provide a set of variables along with the proper classification for that set.
Runtime You provide a set of variables and ask for the proper classification according to the training in Step 1.
Commonly this is used for spam detection. You will provide a corpus of emails or other data along with a "Spam/NotSpam" classification. The library will determine which variables affect the classification and use that to judge future data."

"Again these are just named scopes. You can chain them together, call methods off of them, etc. What’s great about these named scopes is that they do NOT use the :include option, making them much faster. Instead they create a LEFT OUTER JOIN and pass it to the :joins option, which is great for performance. To prove my point here is a quick benchmark from an application I am working on..."