Presumably the two YC companies there have the smallest valuations of the companies on the board, but are representative YC companies that raised Series A's. Loopt should be more expensive than Scribd though, they've raised four times as much funding.

http://www.crunchbase.com/company/scribd http://www.crunchbase.com/company/loopt

I think Boost filed for bankruptcy. They target customers that are less likely to pay their bills. (not sure if this is Ynews worthy.. ;1 )

Yeah, facebook + loopt = killer app