I live by the synchronized fireflies in the Smoky Mountains and have been to Elkmont to see them a few times (despite terrible crowds). But, I have ALSO seen the ones in Malaysia. It's one of the only things I've seen almost all the world's examples of, though thousands of miles apart.
Massive firefly swarms are the only thing I miss about living in Monroeville, Alabama.
Florida is lousy with most other creepy crawlers, but we have a dearth of fireflies for some reason. Increased competition? More predators? just the wrong kind of climate? I don't know why, but we seldom see more than a dozen at a time.