Hmmm... now that I think about lights... my old robot Project Two: Hexem (Dutch Wars 2002/2003) has two eyes who shine red. It is two 50W halogenic lights on one 2 Amp/h 12 Volt Phoebus battery behind red polycarbonate. Beautiful special effect. Another Dutch robot, X-Bot (Dutch Wars 2001), had a halogenic spot light on both sides built into the robot, was nice too.

It doesnt have to be neon in order to be flashy !!!

Also note that Tough As Nails (which we helped build) has 2 red High Density LEDs to mark weapon activation and a normal red LED to mark robot active, there has also been a blue LED to mark weapon solenoid powered but is has been removed and not yet replaced. With the new FRA rules demanding visible signs of activation you might consider installing that as well if you want to go on the live circuit.