The amount of rage the customers will feel towards the makers of whatever non-secure self-driving or "connected" cars receive the ransomware should give those car makers a nice kick in the behind to get their act together.
Then we'll see how quick the car makers will be about implementing features such as "unlocking your car remotely from the beach."
Individual cars doing their own thing, no problem. Cars talking to cloud, big privacy problem, potential security problem. Cars talking to each other locally, smaller privacy problem, but bigger security problem.
You put the stick in someone else's machine and print the files. The stick might be infected after this use.
You don't put the stick back in your machine, because it might be infected.
Do you continue to put it in other people's machines to keep printing?
Don't run or open anything off the stick on your machine and you'll be fine.
Not only can you trivially make such a thing with an arduino but there are also some commercial USB sticks which have a persistent "background" filesystem that cannot be formatted away.
Anything that is run automatically in the background, like the thumbnail services.
Autorun hasn't been a thing in ages.