2003-01-13, 12:25 a.m. : I _was_ going to go to bed two hours ago
Dammit, I can end a phone conversation!
In fact, it's very easy.
You interrupt yourself, say "I love you, good night, goodbye," wait for the other person to make at least one of the same comments, and then you hang up.
You do not get distracted into ten minutes more of conversation.