A smooth streamlined, fast car.
When a highway becomes a neon street, the cars are moving fast! A car, when parked, that is so fab and tricked, is like one on a highway, but since its not moving, its called liquid.
A neon street is a moderately busy highway at night. The cars go so fast, its like a big white or red neon light (especially in slow cameras).
That Mazda RX-8 has features like a Scion! It is liquid neon!