Most of the bad code examples in this post are taken from the CoffeeScript compiler itself. For that I have to say "mea culpa". There's a lot of overly clever and dense bits that have accrued in the compiler over time -- sometimes due to the tangly nature of the codebase, but also sometimes because we tend to use the self-hosted compiler as a test bed for edge cases of combining different language features together.
If you're looking for more regular style, this style guide is a better place to start:
Note: I'm not saying Crockford was singularly responsible for this, but The Good Parts was certainly well-received and very much popularised for it's opinionated views on the language.
Edit: I mean in terms of coding style, CS itself has already cut out a lot of The Bad Parts of JS