What's the nicest thing an absolute stranger has done for or to you?

Me? Here's one.
I have to take an annual brain MRI. I get claustrophobic, but control it with breathing exercises. But one time I freaked out. Asked to be let out. Went for a walk. Still pulse raced.
A tech then sat with me through the scan, his hand on my ankle to reassure me.

Another. Travelling unreserved in Andhra. Had suitcase. Was at door, almost falling out, with nothing to hold on to. Someone also took in my suitcase. (Several people then stood on it, but never mind, whose gonna hold a bag up.) Several hands held in me until the next station.

Jaipur. Came back to hotel with bag full of books I'd bought. Expensive. Some were signed by authors. Left the bag in the rick. Didn't realise until half an hour later, when the desk called to tell me the driver was at the reception with the bag of books. He refused a tip.

.. He said: It's my duty to make sure you go back to your home with good memories of Jaipur. Finally accepted the cost of what would have been his fare back to the hotel.

Bombay, 2 am. Car had flat at the beginning of a flyover. Had never changed a tyre before (& scared of exertion; was recuperating from an illness). Hailed a taxi to take me to a garage where I could bring a mechanic back. Taxi driver said Tchah and changed my tire. Refused cash.

(After much persuasion, agreed to take the equivalent of fare to a nearby garage and back.)