I didn't count Parakey because they were not a regular YC investment. We didn't seed fund them. We were just one of many investors in their series A round.
We usually wouldn't invest that late, but Blake and Joe were so good that it was hard to resist.
No, Parakey is public knowledge. And the reference to "one we can't talk about" first appeared in "Why to Not Not Start a Startup" (http://www.paulgraham.com/notnot.html), which was written before Parakey was acquired.
The impression I got when pg gave the talk at Startup School was that it was some kind of "big company buys little company because they were scared of what they were making" situation. But as far as I know that's all they can say.
PG: Will there be a point when you can talk about the other one that got acquired or is it going to be permanently off limits, at least for the foreseeable future?
They keep telling us we'll be able to talk about it soon, but they've been saying that for a while. It was actually the first acquisition, many months before reddit.
TextPayMe was from Winter 06, though, while the hush-hush acquisition is from the first batch. My bet is on ClickFacts, because it's the only one of the first batch other than Loopt and Reddit/Infogami left standing, it's in a business that an acquirer would keep silent, and the website looks like a post-acquisition company.
You know what'd be really cool is a inkling market on the first YC company to get bought out/go public. I'm buying a craptonne of clickfacts if it gets setup :)
Why does it matter? I don't think entrepreneur implies startup. Someone who starts a restaurant and then a dry cleaner and then a hair salon is still a serial entrepreneur.
I actually find reading your stuff more interesting because you're not what I think of/have a stereotype of as an "entrepreneur" - or at least you don't come across that way in your writing. I get more of a "hacker done good" impression, which is something I can relate to a lot more than "business guy".