Thus one can think of this phenomenon now as
follows: those who have surplus are contributing to the common pool,
using wires which are also held in common; the those who are short of
electricity draw from this common pool but maybe in the future they
will have some surplus to give to the common pool too. And all these
exchanges are accurately accounted for by the meters that turn forward
or backward depending on the direction of flow of power through the
meter. Isn't this the kind of peer-to-peer mechanism you were looking
for. Of course, this is a special case, because the meters are already
there. How can this be extended to other situations and cases? Do we
always need to have metering equipment? Can computers perform a similar
recording function for other peer-to-peer activities/exchanges?