It is a little-known fact that I nearly killed Facebook before it started.
At least, that's what I like to think. Though, perhaps it was inevitable that Facebook would have happened despite my attempted interference. I should make it clear that I'm a huge fan of Facebook and am, well, kind of addicted to it. But imagine how different the world might have been...
You see, back in 2004, Mark Zuckerberg was a student in my Operating Systems course (the much-feared and oft-maligned CS161, widely known as one of the more challenging courses at Harvard). Zuck was one of those students who pretty much nailed the course material without my having to teach it to him; this trait often goes hand-in-hand with having plenty of, shall we say, extracurricular interests and as a result he was not coming to lectures very regularly. At one point I called him to my office to find out where he had been, since class participation (by which I roughly mean, coming to lecture and not falling asleep) is part of the course grade.
Zuck explained that he was very busy starting a new social networking website called Facebook. Besides, he had also been in some trouble with the University for appropriating the digital database of student photo IDs and putting up a kind of "hot-or-not" site where visitors rated the relative attractiveness two randomly-selected pictures. (I like to think that I taught Zuck something about how to implement that in an efficient and deadlock-free manner, but that would no doubt be giving myself too much credit.)
Of course, at that time I thought that social networking sites were a complete waste of time -- both for the users and those developing the sites -- so I earnestly tried to talk Mark out of squandering his precious Harvard education on such a frivolous endeavor. "You think you're going to compete against Friendster and Orkut?" was the general outline of my argument. There were already too many social networking sites out there, I claimed, and building yet another one was clearly a waste of time. After all, didn't he want to graduate? And make an A in CS161 while he was at it?
Zuck was -- remarkably! -- unphased by this line of thinking and went ahead and built Facebook, and just to prove how useless everything we teach about efficiency and careful software design in CS161 really is, he implemented it in PHP. And it worked. Oh yeah, and he managed to grow the site to over 175 million users. So clearly I know pretty much zip when it comes to figuring out what a good startup business strategy is going to be, which explains why I should remain safely ensconced in my office at Harvard.
I want to take a little credit for one aspect of Facebook, though. At a later meeting (after Zuck had left Harvard and gone off to raise millions in capital) we were talking about the future of Facebook and I suggested to him that they really needed to find a way to get people to login to the site regularly. With most social networking sites, you sign up, add your few dozen friends, and maybe for one or two weeks get a kick out of messaging them as they join your friend list. But after that, there's little or no reason to keep returning to the site -- as a result your profile just stagnates. Well, wouldn't you know it -- a few months later Facebook came out with the News Feed feature which shows you what all of your friends are up on on an up-to-the-minute basis. Pure genius! Had I only thought to patent the idea before Mark got his grubby hands on it I would be a very rich (and far less grumpy) man right now.
Ah well. It is, after all, my firmly held conviction that the goal of academia is to broadly disseminate good ideas for others to exploit. All I really need to do is keep publishing papers, and I don't care how many millions that News Feed is worth, it ain't good enough to get into SOSP. Right?
One last thought. If, by any chance, you are thinking about forming your own startup, by all means come talk to me first, and do exactly the opposite of what I tell you. Guaranteed success!
(Update 2/26/09: Some of those commenting here seem to have missed the intended irony of this post. In response to one of the comments, yes, I did in fact invent the Internet. As it turns out, I am also responsible for many other features of Facebook, including the ability to link to your friends, set your status, post photos, and of course -- my favorite feature by far -- superpoke. These were all originally my ideas and I hope you have enjoyed using them during your own Facebook experience. Thanks for giving me the opportunity to clarify!)