With my job here, it's all about banding so if you are in 'band x' then people automatically know in what range your salary is. In North America, it is much more arbitrary, I find and thus people are much more reluctant to talk about it. I've had jobs where we were forbidden to reveal our salaries - grounds for firing.
My experience has been the same as Mrs. Pink. At my UK job, you can find out everyone's band by looking them up on the company intranet; the intranet also shows the salary range for each band.
My sister worked in payroll in the US for many years in the same industry where I work now (financial services). It was very disheartening to her, because people weren't allowed to discuss salaries, and because she had "inside information" she knew that there were people who contributed hardly anything and made shedloads of money, and people who worked their butts off for years and made practically nothing - and had no idea that they weren't being paid enough because nobody was allowed to know what anyone else was making.
In the US, I have also had the experience of sharing salary information being a sackable offense, although in a different industry (advertising).
ETA: I know plenty of people in the US who said they didn't have any money till payday.