There at the creation.
That's one of my favorite phrases. It means you saw a flash of brilliance or caught a truly original moment or, if you spoke up, contributed to an idea or movement that mattered. It means that you were a witness to history. Think about all the imaginary light bulbs it would have been cool to see turn on (like, of course, the invention of the light bulb, whether you think it was Thomas Edison or Joseph Swan). I would like to have been in the brainstorming session for the Declaration of Independence. I would like to have been in Naismith's gym class. I would like to have been in the seat next to J.K. Rowling when she first typed the words "Harry Potter" and realized, even if no one else did yet, that her days of struggling were over. Thanks to Aaron Sorkin and David Fincher, I was there at the creation when Mark Zuckerberg invented Facebook. And it was cool, even if it was just a movie (and one that was robbed of an Oscar).
Those moments are rarely big, I would imagine. The weight of what's to come doesn't usually announce itself in incandescence. Creation myths only make it seem that way.