isn't that special...
One in a billion! How touching! Sounds like you'd have to plow through a billion common people before finding someone as special as I am. So with a world population of 7 billion, there are only about 6 people on the planet whose awesomeness is greater than or exactly equal to my own (presumably greater). Let's not name them, it dilutes the special feeling.
Oops, slow down, it's not me it's my bus ride... there have been 3 billion similar bus rides. Celebrate, Metro, but... this makes my bus ride hugely unspecial. You must have been speaking ironically, essentially controverting the normal purpose of the phrase to instead emphasize how insignificant and ordinary my bus ride is. Well, thanks a lot!