Awesome submission. With the space on the underside of this. You could include slots for Piezo Bimorphic Ceramic Generators to power some LEDs which would look nice in the ends of the circuits. Depending on how much power is generated would determine which Leads light up. If slots where prepared for ceramics at places varing distance from the center lights would light up at different frequencies played through the speaker and at different intensities. Just an idea for you.