Ask HN: What big successes have come from people involved in the startup scene?

It seems to me that the people who start big, successful web businesses do so from outside the 'startup community'. By that I mean that Mark Zuckerberg wasn't on HN (or the 2004 equivilant BBS). He wasn't blogging, or going to meetups - he was quietly building a product (and working freelance I believe).

The same with the Skype guys.

So I'm wondering, can anyone point to a web presence from someone who built something big, but from before they built it? I'm looking to be able to follow someone from 'Hey, is this a good idea?' to 'I've just sold - I'm now an angel'.