Motorola DynaTAC - 1973 Martin Cooper built the world's first cell phone in just 90 days. Without large-scale integrated circuits, engineers had to stuff thousands of resistors, capacitors, inductors, and ceramic filters into a pound package.
RYNO Motors' single-wheeled electric scooter is self-balancing, has a turning radius of zero when stopped, & only takes up about as much space as a folding bicycle -- so it's conceivable that commuters could bring one onto a train.
Aboriginal man using newly installed phone for the first time in Amhem Land, Australia, ca. Photo by Penny Tweedie. This probably isn't supposed to be funny, but just the look on his face.and the bright orange phone.