At Iowa State University, the Ethernet links to dorm rooms are wired up this way. They have small splitter boxes that plug into the wall and provide the two ports. Of course, since these are not real hubs, they can't be chained together, as we found out the hard way. If anyone wants to pick some up, last I knew they were available at the ISU surplus sale. The connections were plenty fast; I'm not sure if they were fully 100-megabit.