If you want a little inspiration, be it a banner you like better, methods of showing your resistance, more discussions, or even just a good laugh to get you through your massively-surveilled day, I have a super-simple suggestion:
Google “Fuck the NSA”.
Don’t stop at web pages, though! Shop it. Checkout the images. Note the discussions groups. Observe the ads that your search will evoke!
Best fun finds:
Teeshirt: “NSA. Finally a government that really listens to its people.”
And an ad: “Wanting casual fun? Try a discreet affair today. 100% safe and anonymous.”