I haven't really seen any research on packet-switched pneumatic tube networks, or any kind of more complicated routing. Every time I've seen one in person it has been more or less point to point, or point to mailroom. I think modern sensing tools, either NFC or high-speed cameras, have the potential to enable some significantly better topologies than what I've seen in real world pneumatic networks.
Also looking at projects like the hyperloop, I'm wondering if a smaller version linking cities would make sense. We already have infrastructure for transporting oil and natural gas through very long pipelines. How about actual packages? If the hyperloop can make sense, I feel like inter-city mini vacuum train probably can as well, and linking two cities together doesn't require any great flexibility.
Also looking at projects like the hyperloop, I'm wondering if a smaller version linking cities would make sense. We already have infrastructure for transporting oil and natural gas through very long pipelines. How about actual packages? If the hyperloop can make sense, I feel like inter-city mini vacuum train probably can as well, and linking two cities together doesn't require any great flexibility.