A note to all those companies, such as iLike, which are desperately adding computer hardware to cope with a surge of visitors from Facebook: Mark Zuckerberg knows your pain. This time last year, the 23-year-old's social network was in a similar position, increasingly popular among college students, and franticly adding servers to keep the site running. And that, an anonymous source close to Greylock tells the London Times, is why Facebook had to sell 10% of the company in a hurry, to the venture firm. "It was a major stuff up," according to a source close to Greylock. "The management should have realised about the expansion and didn't." That equity, which raised $25m, now has a value well in excess $100m. Which would make Facebook's 2006 crisis the most costly hardware crunch in startup history.