I'm there in the edge of a bunch of people who are talking and I'm feeling cut out and awkward and then suddenly I focus on a part of the conversation I know something about and out of desperation to participate I jump in with enthusiasm and then the other people just - silence - and look at me like WTF? And that's the end of the conversation... everyone kind of gives a half-hearted end to what they were saying, makes excuses (or not) and drifts off...

Is that over sharing? maybe.