I actually never saw Thurnderbirds as a kid, but I had an NES game based on it that I really liked. Then at some point, they started showing the show, and I was like, "Hey, this is like that game!" It was always cool - I dig the theme song, which was used in the game too.
Remember watching Thunderbirds, Captain Scarlet and Stingray when I was a kid. The Mysterons used to scare the life out of me.
Admittedly I was born in the 80s so didn't catch any of these when they first aired, but they were still showing these on the BBC in the late 80s/90s. Used to love watching them all.