Reading Dare Obasanjo's blog, I saw reference to this email (jpg) that is linked from Marc Andreessen's Analyzing the Facebook Platform, three weeks in:

"Do you know anybody that may have excess servers we could borrow for the next 5-7 days while we buy new servers of our own?"
Ali Partovi from Ilike, a day after launching on Facebook

Scale problems like this are good to have -- you have lots of customers after all. But, it must be hard to see all your hardware melting as quickly as you add it!