"...and suddenly three turn up at once."
On many of the new (and some old) buses in London are installed TV screens. These show clips from "classic" BBC comedy or wildlife shows, views of the other passengers on the bus, along with bad adverts for local colleges, some basic news and a little tourist info.
What would you put on these screens?
Think of their limitations:
But the advantages are:
Working within these boundaries, come up with content or services, which you think might expand their current use. You might add a very limited amount of extra tech to the system but assume your budget is extremely limited by the Major.