Exiting a conversation

Have you ever ended up in a situation where the person with whom you are talking has no intention of closing the conversation and you are already late for a meeting / bus / whatever? Here are some useful phrases which will help you to exit a conversation in a relatively painless way.

Nice talking to you.
I'm afraid I must be off.
Well, I'm going to circulate. It was good to meet you.
Is that the time? My parking ticket runs out in five minutes!
Is that Jack over there? Excuse me, I really must go and speak to him.
I'm going to get some food. I missed lunch because of the conference call.
I promised to meet someone else. But I'll come back when I've seen him / her.
Look, I really don't have time to chat at the moment. I'll call you tomorrow though.