A method comprises linking a plurality of units with a central server, operating
a virtual game on the server, and offering purchasing options to users of the units
to purchase virtual non-monetary assets for use in the virtual game. Also described
is a system comprising a central server, and a plurality of units linked to the
server via a communication link, wherein a unit of the system includes purchasing
means operable by a user to purchase virtual non-monetary assets for use by a user
in the virtual game.