I had an interview at a company, peak6, that allegedly disallowed any sort of out loud work conversations. From what I was told, they only allowed work conversations over IM. That, and tons of cameras strewn around their overpriced office. In the end, they strung me along for something like 3 months while the employee I was supposed to replace decided to stay in the position.
Be wary of a company that offers so little trust and care for its employees - and potential employees!