TubeFreight

Occasionally one sees a freight train like this one on the London Tube.

If you want to move something smaller, like a parcel, quickly from an office in Fenchurch Street to one in the Fulham Road you give it to a bike messenger.  That person goes off at speed, makes a dent in a BMW bumper ("I didn't see you, mate."), gets sticky red stuff all over the BMW's windscreen, and fails to transfer the parcel.  This is not a very satisfactory solution to the delivery problem.

But it would be quite easy to design a QR-code-based system that allowed you to drop off your parcel at Aldgate station.  Your parcel would slide down a chute to the appropriate platform, having had its destination automatically scanned and having had your account appropriately debited.  There a robot would load it onto the next train (maybe on a parcel and letter rack between the passenger carriages).

At each station the robots would be loading and unloading packages, and swapping them by conveyor to different lines automatically.

When your parcel reached Fulham Broadway that station's robot would unload it and send it on a conveyor out to a collection point on the street.  Its recipient would get a text to say their parcel was ready, whereupon they would stroll to the station, wave their phone at the collection point, and be given their parcel.

The whole system would be fast and fully automatic, and it would make extra income for Transport for London. It would also reduce the need for BMW drivers to keep cleaning their windscreens.