In this paper, we present Wombat, a Wi-Fi tracking platform aiming at improving user awareness toward physical tracking technologies and at experimenting new privacy-preserving mechanisms. Elements of this system are presented along with its architecture. We also present the use of Wombat in the context of a demonstration scenario. We introduce a new privacy-enhancing feature developed on top of Wombat: a Wi-Fi-based opt-out mechanism that allows users to easily express their opt-out decision.