Adding on to your comment, a friend let me read through a beta copy of The Rspec Book last year. At the time, only the first couple chapters were written and it was lacking a lot of content. It was a great resource though, and I would highly recommend it. The final release is due "Soon", and ordering it now gives you access to the current revision of the Beta, which I hear is complete sans-editing. I'm holding out until I can buy a paper copy.
These are all Ruby or Rails specific. Cucumber itself is a DSL to be used along with another language, and there are projects underway to implement Cucumber or Cucumber-like frameworks for other languages like Python, Java and .NET
Thanks. I almost linked to the RSpec Book, but since I haven't read it myself, I didn't feel comfortable endorsing it. Good to know it's shaping up! Maybe I'll have to pick up a copy.
http://www.pragprog.com/titles/achbd/the-rspec-book
Your links to the RailsCasts screencasts are great also. PeepCode also has their Cucumber Screencast that is a little more detailed than RailsCasts.
http://peepcode.com/products/cucumber
These are all Ruby or Rails specific. Cucumber itself is a DSL to be used along with another language, and there are projects underway to implement Cucumber or Cucumber-like frameworks for other languages like Python, Java and .NET