During the last decade, a myriad of new technologies has changed the way society perceives everyday life, embodying the Big Data Era peculiarities. Almost every technological scenario produces an incredible amount of data, from disparate physical sources and at a very different generation rate, creating an interconnected and interdependent network of people and data. For this reason, data has become for companies and organizations a strategical asset to drive businesses, to tailor user-specific services and to obtain a more relevant position on data markets. More and more companies collect and process customers personal data requiring it in exchange for services, forcing users to accept a power unbalanced transaction.