When you are in someone's company, whether on the phone or in person, and something is funny ... laugh. Saying "That's funny" doesn't cut it. In addition, under no circumstances should you ever actually say "LOL". It's revolting when written and even worse when spoken. In an instant message, a little "ha!" goes a long way.

And speaking of going a long way, I'm outta here. I'm going somewhere very far away for a few days, and will post here via telepathy.