Video presentation: https://www.youtube.com/watch?v=jLAFXQ1Av50
Most applications written in Ruby are great, but also exists evil code applying WOP techniques. There are many workarounds in several programming languages, but in Ruby, when it happens, the proportion is bigger. It's very easy to write Ruby code with collateral damage.
You will see a collection of bad Ruby codes, with a description of how these codes affected negatively their applications and the solutions to fix and avoid them. Long classes, coupling, misapplication of OO, illegible code, tangled flows, naming issues and other things you can ever imagine are examples what you'll get.