ZNet has a list of slogans from signs at the RNC protests. Some of the better ones:

Four More Months

George W. Bush is proof that you don’t have to grow up to be President

Texans Against Bush
He ain’t no damn Texan

Who would Jesus bomb?

Let’s not elect him this time either

This is what you get for electing a Republican mayor

One Person, One Vote*
May not apply in certain states

Abstinence in 2004: No Bush, No Dick

I wasn’t using my civil rights anyway

If you can read this, you aren’t the President

I’m marching for my grandma, and she’s pissed.

And the vitriol award goes to:

The Son of Sam did what God told him to, but he only killed 5 or 6 people