Widget-maker RockYou may be willing to spend millions on Facebook applications, but bidders at eBay are a little more discerning. Michael Zhang was first to auction a Facebook application on eBay, and the bidding on his Logbook app closed yesterday. Logbook documents movies, music, and books and ties into Amazon's affiliate-marketing program as a source of revenue. It's less popular and viral than spraypainting your friends' walls — on the other hand, there is the potential for actual revenues — an unusual feature for Facebook's hangers-on. So how much was the winning bid for Logbook?