Not a diss to the cussers but my mother always said it takes more imagination to curse someone out without using profanity. I think the worst one I heard is "It wouldn't be worth the spit to curse you."

http://worthwatering.blogspot.com
Can it be I stayed away too long?/
Did I leave your mind when I was gone?/
It's not my thing trying to get back/
But this time let me tell you where I'm at-- Jackson Five