страничка Андрея Шабашева (http://attend.to/andshab) посвящена
оригинальным загадкам, задачам, викторинам и головоломкам. Кроме того,
есть ссылки на сайты, посвященные головоломкам, задачам и вообще
интеллектуальному досугу.
Matpuzzle: a website with a
lot of mathematical puzzles. It's very interactive. The author often gives
problems he hasn't solved himself yet, readers can respond to that which
might raise new intriguing questions. A lot of links as well.
MathPro Online: a
website containing over 20000 mathematical problems.
See this
page on Yahoo for more links to pages with mathematical puzzles.