My wife and I went riding in Rock Creek Park in Washington D.C. today, on our 16" folding bikes. (A Dahon and a Bike Friday.) A kid, maybe five or six, out with his parents - all of them with bikes, too - saw my bike with wheels the same size as his kiddie bike, and he said, "that's a cool bike!"
I thanked him, and mentioned that his bike was even cooler. "Because it's red, and red bikes are faster. There's a law." Big laugh!