Besides the obvious ones about marriage being a human right and rights not being up for a vote,
A few of the signs I saw today:
Keep your BELIEFS away from my RIGHTS
Another STR8 against H8
I don’t fuck in your polling booth so don’t vote in my bed
When do we get to vote on YOUR marriage?
Brigham Young had 55 wives. I just want 1!
Morman cash lied, a nation cried.
Don’t destroy my marriage. It won’t save yours.
I’m straight. I’m a Californian. And I’m ashamed of Prop 8.
Feel free to add your favorites below (from Seattle or elsewhere).