jimtron
Illuminator
For something a bit more aggressive you could quote from Lucy Mangan's awesome anti-astrology rant in the Guardian, e.g.:
"I'm whatever sign whose prediction this week read, 'On Sunday, a friend who has masqueraded as a rational human being for the 15 years of your acquaintance will stand revealed before you as just another cack-brained, gibbering fool swirling in a festering cesspit of stupidity'."
Just found that--you're right, it is awesome, and very funny:
http://www.guardian.co.uk/theguardian/2005/jan/05/features11
