On many railway stations in Bangladesh you will find a bookshop, not only selling books but also lending books. The idea is that you borrow a book for the duration of your journey, giving back to the station library as you disembark.
Often at the start of the journey an employee from the library will walk through the carriage with an armful of books just in case you missed your chance.
It is a surprisingly popular service. I just wonder how much you can read on a single journey, especially as most passengers seem more intent on consuming all the food they have brought onboard for the journey.