Popular arguments you think Atheists shouldn't use

[RobbyPants]

I've found the least effective arguments I've made involve discussing the morality of God. If you make your case to other non-believers, they'll agree with you, but you're basically preaching to the choir. If you make these arguments to believers, you'll find them make some very creepy-sounding excuses for why God drowns babies, lets us harm each other in the name of free will, killed the first born in the tenth plague, isn't responsible for Original Sin, or isn't going overboard with the whole eternal torture thing. You end up with a worse impression of the apologist, but they will ultimately be unmoved.