I'm just waiting for you stop. I'm waiting patiently... in fact, I'm likely willing you to keep talking for hour, just so I can laugh about it later.
Genties and ladlemen, I have discovered an excellent way to see how self-absorbed or self-obsessed somebody is – you see how long they will talk without interjection.
I once clocked somebody at over ten minutes!
I was, at the time, nodding and being very attentive, so it's not like he would have assumed I wasn't listening. However, unless somebody is outlining a detailed idea of theirs or something of the like, it takes a fair amount of self-obsession to talk for that long. This is a rather enjoyable way to see how much somebody actually cares what you think, and how much they're just talking to hear themselves speak.