A nice, readable overview of the good stuff in JavaScript (and a super-quick summary of the bad). I especially loved when would describe something, and then issue a caution, ending with "this is not a good part."  Like this:

\b was intended to be a word-boundary anchor that would make it easier to match text on word boundaries. Unfortunately, it uses \w to find word boundaries, so it is completely useless for multilingual applications. This is not a good part.