Don't Tread On Me
One of the many license plate options we have here in Virginia is a "Don't Tread On Me" plate. This plate is based on the Gadsden Flag; which was the personal flag of Christopher Gadsden, a brigadier general and commander-in-chief of the Continental Navy during the American Revolution.
The flag is associated with liberty and individualism. This has led to the flag being used by libertarian groups which idealize small government. There are a lot of these license plates here in Northern Virginia; many of them are personalized plates.
I chuckle every time I see them because the drivers are paying an extra $10/yr to the government for these special plates just to advertise that they want less government. If the plates are personalized, it's an extra $10/yr. Idiots.