The Italian newspaper Corriere della Sera discovered that Google didn't go to the mafia district Scampia (Napels) with the Street View car. The surrounding streets are all in Street View but Scampia is a missing piece. The newspaper thinks that Google was scared going in there with the car/tricycle or that the mafia closed a deal with Google.

Via: http://www.telegraaf.nl/digitaal/6347799/__Google_mijdt_maffiabuurt_Napels__.html