For me, this quote from Pride & Prejudice is easily the most recognizable:
He certainly looked at her friend a great deal, but the expression of that look was disputable. It was an earnest, steadfast gaze, but she often doubted whether there were much admiration in it, and sometimes it seemed nothing but absence of mind.
Of course, I do something quite similar–that is, observing people without anything going on upstairs. By the way, one series which I have come to really enjoy reading is written by a lady, Stephanie Barron, who uses Jane Austen herself as the protagonist. While there are apparently some historical mistakes here and there, if you don’t care (or don’t know the mistakes) the books make for very interesting reads. The language is somewhat difficult to understand at first (coming from modern English), but once you get into the first couple of chapters it’s very easy to adjust to the syntax. In fact, the way the characters speak (and act) is half of the series’ charm.