Also there was a talk about Erlang where Joe Armstrong was talking about EHE, but I couldn't find it. I thought it was a joke, but apparently it wasn't.
The latter is undeniably true, even if the former is debatable. I've had to maintain code where PHP variables were assigned from a database then echoed directly into javascript functions and broke more than once because of encoding issues or a lack of necessary escaping -- being able to do crazy things like that is very flexible and fast, but it can also lead to some horrible messes if you don't know what you're doing.
