There are some things that AIs on some games do, yet don't do in others. This begs the question, "Why"? So here's a little recap of what some games do, yet others don't. I'm trying to keep this simple, and who knows, maybe somthing like this will show up?

Taunting; A'la Age of Empires, Empire Earth. Advancing to an age will get a quick one-liner from an enemy, and your enemy getting the upper hand will prompt a small verbal slam. In turn, send a taunt, and the AI returns a quip right back.
Spring Applications: Destroy some resource buildings to get one of 5 randomly-selected lines. Start getting base-raped and it'll brag about how much your4n00b.
More to come later. Anyone else?