The lights sure look cool on the cars in the Rolex 24.

[downtowndeco]

Lighted number plates along with other lighted accents on the cars. The next innovation for slot cars?

[Bluevista]

Those lights are called the "Leader Light System" and show what position the car is in within its class. Race series slot cars have them, they just don't light up. I guess it could be done to scale by an electronics guru if you wanted it to really work?
I already have my tickets for the May 5th IMSA race at Mid-Ohio,. I'll be sitting at the top of grandstand one at times, be there or be square.

[RichD]

Miller Engineering makes small animated lighted signs, those are about the thickness of cardstock. The electronic parts of the signs are more like the circuit board used with a digital car however. Since a slot car moves faster in scale than a 1:1 car the lighted signs would not necessarily have to be animated, so the electronics could be more compact.

[Modlerbob]

I had to stay home and watch on NBC/SN. They had pretty good coverage. The weather this year was so much better than in the recent past.