Super Mario, Sonic the Hedgehog, Donkey Kong, and good ol' Captain Falcon.
When I was younger, and a car sped down the road really fast (for some reason they always came to our street) the noise would scare me, but my dad would always assure me it was just Sonic the Hedgehog speeding by the save the world.
EDIT: As a previous poster said, I also imagined myself as being way past cool like Sonic. I would run everywhere, and my love for the blue hedgehog actually propelled me to be one of the fastest kids around. I still am, although I don't run much anymore.