Next generation mobile devices will allow users to share and pass
information within anonymous groups of people in an ad hoc manner.
This will smooth the path for many kinds of new mobile commerce
In this paper we present a mobile commerce application that
is part of the *blinded* research project. It allows the dissemination
of digital advertisements among interested mobile users. To offer
an incentive, an anonymous bonus point system rewards users, who help to carry an advertisement from a merchant to a customer.
This work includes a formal description of our bonus point model,
a thorough discussion on the security goals, their realization and
some first results about crypto-operation runtime behavior on a
state-of-the-art PDA. Furthermore, our early prototype is presented.