Huge planet known as the "Savage Twister"

[CaptSpoogy]

This is perhaps my favorite line in Space Empires IV...

Runner up?

"Beware of strange Warp Points" or
"Mineral Planets are the best" with the funny looking Norak guy...

[Puke]

I prefer the ones on rock/none worlds that describe the unique atmospheric characteristics.

[dmm]

I like to get the enemy down to almost nothing, then send him the "Your progress is impressive" message.

[chilla37]

I wish there was a message class of "Taunt Opponent"! Then I could use it to keep the AI mad when they get a little too friendly. (I hate it when I'm at war with a "brotherly" opponent.)