This is really separate from the previous PR kind of inquiry.

Advertising. The con season is coming up and we want to make a splash.

Maybe stickers, T-Shirts, flyers...
Any other ideas? Any thoughts on how the above works in reality instead of how we hope it'll work? Any known resources for the above?

There is nothing (nothing) that I have seen that compares with the impact of having an excited designer (or knowledgeable player) demonstrating the system.

My standards are these:

• A good demo should become interesting to the players in less than three minutes. "Instantly" is even better.
• A good demo should reliably be done (start to finish) in fifteen minutes.
• It should have shown enough of the rules that the players could enjoyably play a four hour session without learning more.
• It should, above all, leave them wanting to play that four hour session, as soon as possible, with their friends.

My advice? Take the time you would spend making up knick-knacks, and spend it on perfecting your demo... and even on training friends and partners to demo in your absence.