November, December, the end of the year is coming. Japanese companies use this opportunity to visit companies they are dealing with all the year (customers, suppliers...) and bring them next year's calendar (カレンダー or 暦-Koyomi).
When people give a calendar to a company, they usually say : 今年もお世話になりました。来年もよろしくお願いいたします。(kotoshi mo osewa ni narimashita. rainen mo yoroshiku onegai itashimasu)
They thank companies for their cooperation, and express their will to maintain a good business relationship for the coming year.
Companies make their own calendar with their logo and name written on, and bring it to other companies : there is also a promotion end.
Those calendars are distributed from mid-November until the end of December. This business manner is practiced since hundreds of years.
In 1600, calendars were already distributed.
At this period, people working in sort of shops were able to read and count whereas a lot of people couldn't.
So they created calendars understandable for everyone. Instead of numbers or words, they used images of everyday life or season event. (picture from : http://hironoiwate.blog.fc2.com/blog-entry-5.html).
Shops also added on calendars their shop's name, and distributed it to people. Those calendars were called : 絵暦 (E-Goyomi).
Japanese companies perpetuate this habit, and continue to bring every year calendars. It could be more than 1000 per company, it depends of the company size and of the type of business.
Japanese companies also bring a lot of other gift among the year: towels, fruits, beers, juices... to demonstrate their gratitude and keep a good relationship.