It depends--do I receive 1 cent per email received at yahoo? In all seriousness, the micropayments concept has been floated long ago as a spam-fighting measure

It depends--do I receive 1 cent per email received at yahoo? In all seriousness, the micropayments concept has been floated long ago as a spam-fighting measure; the first problem is that just about every provider has to do it before it becomes useful enough to warrant the cost--which incurs a large first-mover penalty.