I am so sorry that I forgot Martin Gardner's birthday on October 21st. He has been gone for a while now, but he would have been 100 years old this year.
If you don't know his name, and you are interested in recreational mathematology you need to learn it. Strickly speaking is is not a mathematician, he is a journalist. But he has written more on the topic of mathematics (in particular recreational mathematics) than any mathematician I know of.
Many of you have been his fans for years, and you may have become interested in Mathematics because of Martin Gardner's books and articles. If not, please see the references, especially the last one to learn more about him. And start collecting his books.